diff --git a/lib/NGCP/Panel/Controller/API/Contacts.pm b/lib/NGCP/Panel/Controller/API/SystemContacts.pm
similarity index 59%
rename from lib/NGCP/Panel/Controller/API/Contacts.pm
rename to lib/NGCP/Panel/Controller/API/SystemContacts.pm
index 860594c7bd..6fabf2b30b 100644
--- a/lib/NGCP/Panel/Controller/API/Contacts.pm
+++ b/lib/NGCP/Panel/Controller/API/SystemContacts.pm
@@ -1,14 +1,12 @@
-package NGCP::Panel::Controller::API::Contacts;
+package NGCP::Panel::Controller::API::SystemContacts;
 use Sipwise::Base;
 use namespace::sweep;
 use boolean qw(true);
 use Data::HAL qw();
 use Data::HAL::Link qw();
-use Data::Record qw();
 use HTTP::Headers qw();
 use HTTP::Status qw(:constants);
 use MooseX::ClassAttribute qw(class_has);
-use NGCP::Panel::Form::Contact::Admin qw();
 use NGCP::Panel::Form::Contact::Reseller qw();
 use Path::Tiny qw(path);
 use Safe::Isa qw($_isa);
@@ -20,8 +18,9 @@ require Catalyst::ActionRole::RequireSSL;
 
 with 'NGCP::Panel::Role::API';
 
-class_has('dispatch_path', is => 'ro', default => '/api/contacts/');
-class_has('relation', is => 'ro', default => 'http://purl.org/sipwise/ngcp-api/#rel-contacts');
+class_has('resource_name', is => 'ro', default => 'systemcontacts');
+class_has('dispatch_path', is => 'ro', default => '/api/systemcontacts/');
+class_has('relation', is => 'ro', default => 'http://purl.org/sipwise/ngcp-api/#rel-systemcontacts');
 
 __PACKAGE__->config(
     action => {
@@ -49,20 +48,19 @@ sub GET :Allow {
     my $page = $c->request->params->{page} // 1;
     my $rows = $c->request->params->{rows} // 10;
     {
-        last if $self->cached($c);
         my $contacts = $c->model('DB')->resultset('contacts');
-        $self->last_modified($contacts->get_column('modify_timestamp')->max_rs->single->modify_timestamp);
         my $total_count = int($contacts->count);
         $contacts = $contacts->search(undef, {
             page => $page,
             rows => $rows,
         });
         my (@embedded, @links);
+        my $form = NGCP::Panel::Form::Contact::Reseller->new;
         for my $contact ($contacts->search({}, {order_by => {-asc => 'me.id'}, prefetch => ['reseller']})->all) {
-            push @embedded, $self->hal_from_contact($contact);
+            push @embedded, $self->hal_from_contact($c, $contact, $form);
             push @links, Data::HAL::Link->new(
-                relation => 'ngcp:contacts',
-                href     => sprintf('/api/contacts/%d', $contact->id),
+                relation => 'ngcp:'.$self->resource_name,
+                href     => sprintf('/%s%d', $c->request->path, $contact->id),
             );
         }
         push @links,
@@ -73,12 +71,12 @@ sub GET :Allow {
                 templated => true,
             ),
             Data::HAL::Link->new(relation => 'profile', href => 'http://purl.org/sipwise/ngcp-api/'),
-            Data::HAL::Link->new(relation => 'self', href => "/api/contacts/?page=$page&rows=$rows");
+            Data::HAL::Link->new(relation => 'self', href => sprintf('/%s?page=%s&rows=%s', $c->request->path, $page, $rows));
         if(($total_count / $rows) > $page ) {
-            push @links, Data::HAL::Link->new(relation => 'next', href => "/api/contacts/?page=".($page+1)."&rows=$rows"),
+            push @links, Data::HAL::Link->new(relation => 'next', href => sprintf('/%s?page=%d&rows=%d', $c->request->path, $page + 1, $rows));
         }
         if($page > 1) {
-            push @links, Data::HAL::Link->new(relation => 'prev', href => "/api/contacts/?page=".($page-1)."&rows=$rows");
+            push @links, Data::HAL::Link->new(relation => 'prev', href => sprintf('/%s?page=%d&rows=%d', $c->request->path, $page - 1, $rows));
         }
 
         my $hal = Data::HAL->new(
@@ -88,18 +86,14 @@ sub GET :Allow {
         $hal->resource({
             total_count => $total_count,
         });
+        my $rname = $self->resource_name;
         my $response = HTTP::Response->new(HTTP_OK, undef, HTTP::Headers->new(
             (map { # XXX Data::HAL must be able to generate links with multiple relations
-                s|rel="(http://purl.org/sipwise/ngcp-api/#rel-contacts)"|rel="item $1"|;
+                s|rel="(http://purl.org/sipwise/ngcp-api/#rel-$rname)"|rel="item $1"|;
                 s/rel=self/rel="collection self"/;
                 $_
             } $hal->http_headers),
-            Cache_Control => 'no-cache, private',
-            ETag => $self->etag($hal->as_json),
-            Expires => DateTime::Format::HTTP->format_datetime($self->expires),
-            Last_Modified => DateTime::Format::HTTP->format_datetime($self->last_modified),
         ), $hal->as_json);
-        $c->cache->set($c->request->uri->canonical->as_string, $response, { expires_at => $self->expires->epoch });
         $c->response->headers($response->headers);
         $c->response->body($response->content);
         return;
@@ -119,8 +113,7 @@ sub OPTIONS :Allow {
     my $allowed_methods = $self->allowed_methods;
     $c->response->headers(HTTP::Headers->new(
         Allow => $allowed_methods->join(', '),
-        Accept_Post => 'application/hal+json; profile=http://purl.org/sipwise/ngcp-api/#rel-contacts',
-        Content_Language => 'en',
+        Accept_Post => 'application/hal+json; profile=http://purl.org/sipwise/ngcp-api/#rel-'.$self->resource_name,
     ));
     $c->response->content_type('application/json');
     $c->response->body(JSON::to_json({ methods => $allowed_methods })."\n");
@@ -137,34 +130,13 @@ sub POST :Allow {
         );
         last unless $resource;
 
-        my $contact_form;
-        if($c->user->roles eq "api_admin") {
-            if($resource->{reseller_id}) {
-                $contact_form = NGCP::Panel::Form::Contact::Admin->new;
-            } else {
-                $contact_form = NGCP::Panel::Form::Contact::Reseller->new;
-                delete $resource->{reseller_id};
-            }
-        } else {
-            $contact_form = NGCP::Panel::Form::Contact::Reseller->new;
-            $resource->{reseller_id} = $c->user->reseller_id;
-        }
+        my $form = NGCP::Panel::Form::Contact::Reseller->new;
         last unless $self->validate_form(
             c => $c,
             resource => $resource,
-            form => $contact_form,
+            form => $form,
         );
 
-        if($c->user->roles eq "api_admin" && !exists $resource->{reseller_id}) {
-            # admins can pass a contact without reseller_id
-        } else {
-            my $reseller = $c->model('DB')->resultset('resellers')->find($resource->{reseller_id});
-            unless($reseller) {
-                $self->error($c, HTTP_UNPROCESSABLE_ENTITY, "Invalid reseller_id."); # TODO: log error, ...
-                last;
-            }
-        }
-
         my $now = DateTime->now;
         $resource->{create_timestamp} = $now;
         $resource->{modify_timestamp} = $now;
@@ -173,24 +145,21 @@ sub POST :Allow {
             $contact = $c->model('DB')->resultset('contacts')->create($resource);
         } catch($e) {
             $c->log->error("failed to create contact: $e"); # TODO: user, message, trace, ...
-            $self->error($c, HTTP_INTERNAL_SERVER_ERROR, "failed to create contact");
+            $self->error($c, HTTP_INTERNAL_SERVER_ERROR, "Failed to create contact.");
             last;
         }
 
-        $c->cache->remove($c->request->uri->canonical->as_string);
         $c->response->status(HTTP_CREATED);
-        $c->response->header(Location => sprintf('/api/contacts/%d', $contact->id));
+        $c->response->header(Location => sprintf('/%s%d', $c->request->path, $contact->id));
         $c->response->body(q());
     }
     return;
 }
 
 sub hal_from_contact : Private {
-    my ($self, $contact) = @_;
-    # XXX invalid 00-00-00 dates
-    my %resource = $contact->get_inflated_columns;
-    my $id = delete $resource{id};
+    my ($self, $c, $contact, $form) = @_;
 
+    my %resource = $contact->get_inflated_columns;
 
     my $hal = Data::HAL->new(
         links => [
@@ -200,38 +169,29 @@ sub hal_from_contact : Private {
                 name => 'ngcp',
                 templated => true,
             ),
-            Data::HAL::Link->new(relation => 'collection', href => '/api/contacts/'),
+            Data::HAL::Link->new(relation => 'collection', href => sprintf('/%s', $c->request->path)),
             Data::HAL::Link->new(relation => 'profile', href => 'http://purl.org/sipwise/ngcp-api/'),
-            Data::HAL::Link->new(relation => 'self', href => "/api/contacts/$id"),
+            Data::HAL::Link->new(relation => 'self', href => sprintf("/%s%d", $c->request->path, $contact->id)),
             $contact->reseller
                 ? Data::HAL::Link->new(
                     relation => 'ngcp:resellers',
                     href => sprintf('/api/resellers/%d', $contact->reseller_id),
                 ) : (),
         ],
-        relation => 'ngcp:contacts',
+        relation => 'ngcp:'.$self->resource_name,
+    );
+
+    return unless $self->validate_form(
+        c => $c,
+        form => $form,
+        resource => \%resource,
+        run => 0,
     );
 
-    my %fields = map { $_->name => undef } grep { 'Text' eq $_->type || 'Email' eq $_->type }
-        NGCP::Panel::Form::Contact::Reseller->new->fields;
-    for my $k (keys %resource) {
-        delete $resource{$k} unless exists $fields{$k};
-        $resource{$k} = DateTime::Format::RFC3339->format_datetime($resource{$k}) if $resource{$k}->$_isa('DateTime');
-    }
     $hal->resource({%resource});
     return $hal;
 }
 
-sub valid_id : Private {
-    my ($self, $c, $id) = @_;
-    return 1 if $id->is_integer;
-    $c->response->status(HTTP_BAD_REQUEST);
-    $c->response->header('Content-Language' => 'en');
-    $c->response->content_type('application/xhtml+xml');
-    $c->stash(template => 'api/invalid_query_parameter.tt', key => 'id');
-    return;
-}
-
 sub end : Private {
     my ($self, $c) = @_;
 
diff --git a/lib/NGCP/Panel/Controller/API/ContactsItem.pm b/lib/NGCP/Panel/Controller/API/SystemContactsItem.pm
similarity index 70%
rename from lib/NGCP/Panel/Controller/API/ContactsItem.pm
rename to lib/NGCP/Panel/Controller/API/SystemContactsItem.pm
index 151f7cbd11..ef6acfea80 100644
--- a/lib/NGCP/Panel/Controller/API/ContactsItem.pm
+++ b/lib/NGCP/Panel/Controller/API/SystemContactsItem.pm
@@ -1,19 +1,13 @@
-package NGCP::Panel::Controller::API::ContactsItem;
+package NGCP::Panel::Controller::API::SystemContactsItem;
 use Sipwise::Base;
 use namespace::sweep;
 use boolean qw(true);
 use Data::HAL qw();
 use Data::HAL::Link qw();
-use Data::Record qw();
-use DateTime::Format::HTTP qw();
-use DateTime::Format::RFC3339 qw();
-use Digest::SHA3 qw(sha3_256_base64);
 use HTTP::Headers qw();
 use HTTP::Status qw(:constants);
-use JSON qw();
 use MooseX::ClassAttribute qw(class_has);
 use NGCP::Panel::Form::Contact::Reseller qw();
-use NGCP::Panel::Form::Contact::Admin qw();
 use NGCP::Panel::Utils::ValidateJSON qw();
 use Path::Tiny qw(path);
 use Safe::Isa qw($_isa);
@@ -24,8 +18,9 @@ require Catalyst::ActionRole::RequireSSL;
 
 with 'NGCP::Panel::Role::API';
 
-class_has('dispatch_path', is => 'ro', default => '/api/contacts/');
-class_has('relation', is => 'ro', default => 'http://purl.org/sipwise/ngcp-api/#rel-contacts');
+class_has('resource_name', is => 'ro', default => 'systemcontacts');
+class_has('dispatch_path', is => 'ro', default => '/api/systemcontacts/');
+class_has('relation', is => 'ro', default => 'http://purl.org/sipwise/ngcp-api/#rel-systemcontacts');
 
 __PACKAGE__->config(
     action => {
@@ -52,23 +47,20 @@ sub GET :Allow {
     my ($self, $c, $id) = @_;
     {
         last unless $self->valid_id($c, $id);
-        last if $self->cached($c);
         my $contact = $self->contact_by_id($c, $id);
         last unless $self->resource_exists($c, contact => $contact);
 
-        my $hal = $self->hal_from_contact($c, $contact);
+        my $form = NGCP::Panel::Form::Contact::Reseller->new;
+        my $hal = $self->hal_from_contact($c, $contact, $form);
+
+        # TODO: we don't need reseller stuff here!
         my $response = HTTP::Response->new(HTTP_OK, undef, HTTP::Headers->new(
             (map { # XXX Data::HAL must be able to generate links with multiple relations
                 s|rel="(http://purl.org/sipwise/ngcp-api/#rel-resellers)"|rel="item $1"|;
                 s/rel=self/rel="item self"/;
                 $_
             } $hal->http_headers),
-            Cache_Control => 'no-cache, private',
-            ETag => $self->etag($hal->as_json),
-            Expires => DateTime::Format::HTTP->format_datetime($self->expires),
-            Last_Modified => DateTime::Format::HTTP->format_datetime($self->last_modified),
         ), $hal->as_json);
-        $c->cache->set($c->request->uri->canonical->as_string, $response, { expires_at => $self->expires->epoch });
         $c->response->headers($response->headers);
         $c->response->body($response->content);
         return;
@@ -89,7 +81,6 @@ sub OPTIONS :Allow {
     $c->response->headers(HTTP::Headers->new(
         Allow => $allowed_methods->join(', '),
         Accept_Patch => 'application/json-patch+json',
-        Content_Language => 'en',
     ));
     $c->response->content_type('application/json');
     $c->response->body(JSON::to_json({ methods => $allowed_methods })."\n");
@@ -234,84 +225,29 @@ sub PUT :Allow {
         my $preference = $self->require_preference($c);
         last unless $preference;
 
-        my $contact;
-        my $cached = $c->cache->get($c->request->uri->canonical->as_string);
-        if ($cached) {
-            try {
-                die 'not a response object' unless $cached->$_isa('HTTP::Response');
-            } catch($e) {
-                die "cache poisoned: $e";
-            };
-            last unless $self->valid_precondition($c, $cached->header('ETag'), 'contact');
-            try {
-=pod            
-                # TODO: what does this actually do? we need to go to DB for fetching the
-                # contact anyways, no?
-                NGCP::Panel::Utils::ValidateJSON->new($cached->content);
-                $resource = JSON::decode_json($cached->content);
-                delete $resource->{_links};
-                delete $resource->{_embedded};
-                $c->log->debug("+++++++++++++++ got contact for PUT from cache");
-=cut
-            } catch($e) {
-                die "cache poisoned: $e";
-            };
-        } else {
-            if ('*' eq $c->request->header('If-Match')) {
-                $contact = $self->contact_by_id($c, $id);
-                last unless $self->resource_exists($c, contact => $contact);
-            } else {
-                $self->error($c, HTTP_PRECONDITION_FAILED, "This 'contact' entity cannot be found, it is either expired or does not exist. Fetch a fresh one.");
-                last;
-            }
-        }
-
-        my $contact_form;
-        my $undef_reseller;
-        if($c->user->roles eq "api_admin") {
-            if(defined $resource->{reseller_id}) {
-                $contact_form = NGCP::Panel::Form::Contact::Admin->new;
-            } else {
-                $contact_form = NGCP::Panel::Form::Contact::Reseller->new;
-                delete $resource->{reseller_id};
-                $undef_reseller = 1;
-            }
-        } else {
-            $contact_form = NGCP::Panel::Form::Contact::Reseller->new;
-            # keep the reseller_id as is if a reseller is updating a contact
-            delete $resource->{reseller_id};
-        }
-
+        my $form = NGCP::Panel::Form::Contact::Reseller->new;
         last unless $self->validate_form(
             c => $c,
             resource => $resource,
-            form => $contact_form,
+            form => $form,
         );
-        $resource->{reseller_id} = undef 
-            if($undef_reseller);
 
         $resource->{modify_timestamp} = DateTime->now;
-        $contact = $self->contact_by_id($c, $id) unless $contact;
+        my $contact = $self->contact_by_id($c, $id);
         $contact->update($resource);
         $guard->commit;
 
         if ('minimal' eq $preference) {
-            $c->cache->remove($c->request->uri->canonical->as_string);
             $c->response->status(HTTP_NO_CONTENT);
             $c->response->header(Preference_Applied => 'return=minimal');
             $c->response->body(q());
         } else {
-            my $hal = $self->hal_from_contact($c, $contact);
+            my $hal = $self->hal_from_contact($c, $contact, $form);
             my $response = HTTP::Response->new(HTTP_OK, undef, HTTP::Headers->new(
                 $hal->http_headers,
-                Cache_Control => 'no-cache, private',
-                ETag => $self->etag($hal->as_json),
-                Expires => DateTime::Format::HTTP->format_datetime($self->expires),
-                Last_Modified => DateTime::Format::HTTP->format_datetime($self->last_modified),
             ), $hal->as_json);
-            $c->cache->set($c->request->uri->canonical->as_string, $response, { expires_at => $self->expires->epoch });
             $c->response->headers($response->headers);
-            $c->response->header(Preference_Applied => 'return=representation'); # don't cache this
+            $c->response->header(Preference_Applied => 'return=representation');
             $c->response->body($response->content);
         }
     }
@@ -335,8 +271,6 @@ sub DELETE :Allow {
         }
         $guard->commit;
 
-        $c->cache->remove($c->request->uri->canonical->as_string);
-
         $c->response->status(HTTP_NO_CONTENT);
         $c->response->body(q());
     }
@@ -345,26 +279,17 @@ sub DELETE :Allow {
 
 sub contact_by_id : Private {
     my ($self, $c, $id) = @_;
-    my $contact_rs = $c->model('DB')->resultset('contacts');
-    if($c->user->roles eq "api_admin") {
-        # admin can handle all contacts
-    } elsif($c->user->roles eq "api_reseller") {
-        $contact_rs = $contact_rs->search({
-            reseller_id => $c->user->reseller_id,
-        });
-    } else {
-        # TODO: for subscribers etc?
-        return;
-    }
+
+    # we only return system contacts, that is, a contact without reseller
+    my $contact_rs = $c->model('DB')->resultset('contacts')
+        ->search({ reseller_id => undef });
     return $contact_rs->find({'me.id' => $id});
 }
 
 sub hal_from_contact : Private {
     my ($self, $c, $contact) = @_;
-    # XXX invalid 00-00-00 dates
     my %resource = $contact->get_inflated_columns;
     my $id = $resource{id};
-    $self->last_modified(delete $resource{modify_timestamp});
 
     my $hal = Data::HAL->new(
         links => [
@@ -374,24 +299,14 @@ sub hal_from_contact : Private {
                 name => 'ngcp',
                 templated => true,
             ),
-            Data::HAL::Link->new(relation => 'collection', href => '/api/contacts/'),
+            Data::HAL::Link->new(relation => 'collection', href => sprintf("/api/%s/", $self->resource_name)),
             Data::HAL::Link->new(relation => 'profile', href => 'http://purl.org/sipwise/ngcp-api/'),
-            Data::HAL::Link->new(relation => 'self', href => "/api/contacts/$id"),
-            $contact->reseller
-                ? Data::HAL::Link->new(
-                    relation => 'ngcp:resellers',
-                    href => sprintf('/api/resellers/%d', $contact->reseller_id),
-                ) : (),
+            Data::HAL::Link->new(relation => 'self', href => sprintf("/%s", $c->request->path)),
         ],
-        relation => 'ngcp:contacts',
+        relation => 'ngcp:'.$self->resource_name,
     );
 
-    my $form;
-    if($c->user->roles eq "api_admin") {
-        $form = NGCP::Panel::Form::Contact::Admin->new;
-    } else {
-        $form = NGCP::Panel::Form::Contact::Reseller->new;
-    }
+    my $form = NGCP::Panel::Form::Contact::Reseller->new;
     $self->validate_form(
         c => $c,
         resource => \%resource,
diff --git a/lib/NGCP/Panel/Role/API.pm b/lib/NGCP/Panel/Role/API.pm
index c455c9cb35..5ef956586f 100644
--- a/lib/NGCP/Panel/Role/API.pm
+++ b/lib/NGCP/Panel/Role/API.pm
@@ -99,6 +99,7 @@ sub validate_form {
 
     # move {xxx}{id} back into {xxx_id} for DB
     foreach my $key(@normalized) {
+        next unless(exists $resource->{$key});
         $resource->{$key . '_id'} = defined($resource->{$key}{id}) ?
             int($resource->{$key}{id}) :
             $resource->{$key}{id};
@@ -177,6 +178,8 @@ sub require_wellformed_json {
     return 1;
 }
 
+=pod
+# don't use caching for now, keep it as simple as possible
 sub cached {
     my ($self, $c) = @_;
     my $response = $c->cache->get($c->request->uri->canonical->as_string);
@@ -213,6 +216,7 @@ sub expires {
     my ($self) = @_;
     return DateTime->now->clone->add(years => 1); # XXX insert product end-of-life
 }
+=cut
 
 sub allowed_methods {
     my ($self) = @_;
diff --git a/t/api-contracts.t b/t/api-contracts.t
index a44687ab6b..ad58921f1b 100644
--- a/t/api-contracts.t
+++ b/t/api-contracts.t
@@ -1 +1,6 @@
 # TODO: try to set reseller_id of contact of a system contract, which should fail
+
+#    TODO: try to delete used contact
+#    $req = HTTP::Request->new('DELETE', $uri.'/api/systemcontacts/1');
+#    $res = $ua->request($req);
+#    ok($res->code == 423, "check delete of used contact");
diff --git a/t/api-contacts.t b/t/api-systemcontacts.t
similarity index 74%
rename from t/api-contacts.t
rename to t/api-systemcontacts.t
index 7bd8d4b63f..dc04e65012 100644
--- a/t/api-contacts.t
+++ b/t/api-systemcontacts.t
@@ -23,10 +23,10 @@ $ua->ssl_opts(
 
 # OPTIONS tests
 {
-    $req = HTTP::Request->new('OPTIONS', $uri.'/api/contacts/');
+    $req = HTTP::Request->new('OPTIONS', $uri.'/api/systemcontacts/');
     $res = $ua->request($req);
     ok($res->code == 200, "check options request");
-    ok($res->header('Accept-Post') eq "application/hal+json; profile=http://purl.org/sipwise/ngcp-api/#rel-contacts", "check Accept-Post header in options response");
+    ok($res->header('Accept-Post') eq "application/hal+json; profile=http://purl.org/sipwise/ngcp-api/#rel-systemcontacts", "check Accept-Post header in options response");
     my $opts = JSON::from_json($res->decoded_content);
     my @hopts = split /\s*,\s*/, $res->header('Allow');
     ok(exists $opts->{methods} && ref $opts->{methods} eq "ARRAY", "check for valid 'methods' in body");
@@ -43,13 +43,12 @@ my @allcontacts = ();
     # create 6 new system contacts (no reseller)
     my %contacts = ();
     for(my $i = 1; $i <= 6; ++$i) {
-        $req = HTTP::Request->new('POST', $uri.'/api/contacts/');
+        $req = HTTP::Request->new('POST', $uri.'/api/systemcontacts/');
         $req->header('Content-Type' => 'application/json');
         $req->content(JSON::to_json({
             firstname => "Test_First_$i",
             lastname  => "Test_Last_$i",
             email     => "test.$i\@test.invalid",
-            reseller_id => 1,
         }));
         $res = $ua->request($req);
         ok($res->code == 201, "create test contact $i");
@@ -59,7 +58,7 @@ my @allcontacts = ();
     }
 
     # try to create invalid contact without email
-    $req = HTTP::Request->new('POST', $uri.'/api/contacts/');
+    $req = HTTP::Request->new('POST', $uri.'/api/systemcontacts/');
     $req->header('Content-Type' => 'application/json');
     $req->content(JSON::to_json({
         firstname => "Test_First_invalid",
@@ -71,23 +70,8 @@ my @allcontacts = ();
     ok($email_err->{code} eq "422", "check error code in body");
     ok($email_err->{message} =~ /field=\'email\'/, "check error message in body");
 
-    # try to create invalid contact with invalid reseller_id
-    $req = HTTP::Request->new('POST', $uri.'/api/contacts/');
-    $req->header('Content-Type' => 'application/json');
-    $req->content(JSON::to_json({
-        firstname => "Test_First_invalid",
-        lastname  => "Test_Last_invalid",
-        email     => "test.invalid\@test.invalid",
-        reseller_id => 99999,
-    }));
-    $res = $ua->request($req);
-    ok($res->code == 422, "create test contact with invalid reseller_id");
-    my $reseller_err = JSON::from_json($res->decoded_content);
-    ok($reseller_err->{code} eq "422", "check error code in body");
-    ok($reseller_err->{message} =~ /Invalid reseller_id/, "check error message in body");
-
     # iterate over contacts collection to check next/prev links
-    my $nexturi = $uri.'/api/contacts/?page=1&rows=5';
+    my $nexturi = $uri.'/api/systemcontacts/?page=1&rows=5';
     do {
         $res = $ua->get($nexturi);
         ok($res->code == 200, "fetch contacts page");
@@ -120,15 +104,15 @@ my @allcontacts = ();
         }
 
         # TODO: I'd expect that to be an array ref in any case!
-        ok((ref $collection->{_links}->{'ngcp:contacts'} eq "ARRAY" ||
-            ref $collection->{_links}->{'ngcp:contacts'} eq "HASH"), "check if 'ngcp:contacts' is array/hash-ref");
+        ok((ref $collection->{_links}->{'ngcp:systemcontacts'} eq "ARRAY" ||
+            ref $collection->{_links}->{'ngcp:systemcontacts'} eq "HASH"), "check if 'ngcp:contacts' is array/hash-ref");
 
         # remove any contact we find in the collection for later check
-        if(ref $collection->{_links}->{'ngcp:contacts'} eq "HASH") {
+        if(ref $collection->{_links}->{'ngcp:systemcontacts'} eq "HASH") {
             # TODO: handle hashref
-            delete $contacts{$collection->{_links}->{'ngcp:contacts'}->{href}};
+            delete $contacts{$collection->{_links}->{'ngcp:systemcontacts'}->{href}};
         } else {
-            foreach my $c(@{ $collection->{_links}->{'ngcp:contacts'} }) {
+            foreach my $c(@{ $collection->{_links}->{'ngcp:systemcontacts'} }) {
                 delete $contacts{$c->{href}};
             }
         }
@@ -161,10 +145,7 @@ my @allcontacts = ();
     ok(exists $contact->{firstname}, "check existence of firstname");
     ok(exists $contact->{lastname}, "check existence of lastname");
     ok(exists $contact->{email}, "check existence of email");
-    ok(exists $contact->{reseller_id}, "check existence of reseller_id");
-    if(defined $contact->{reseller_id}) {
-        ok($res->decoded_content =~ /\"reseller_id\"\s*:\s*\d+/, "check if reseller_id is number");
-    }
+    ok(!exists $contact->{reseller_id}, "check absence of reseller_id");
     
     # PUT same result again
     my $old_contact = { %$contact };
@@ -217,24 +198,14 @@ my @allcontacts = ();
     my $new_contact = JSON::from_json($res->decoded_content);
     is_deeply($old_contact, $new_contact, "check put if unmodified put returns the same");
 
-    # check if a contact without reseller doesn't have a resellers link
-    $contact->{reseller_id} = undef;
-    $req->content(JSON::to_json($contact));
-    $res = $ua->request($req);
-    ok($res->code == 200, "check put successful");
-    $new_contact = JSON::from_json($res->decoded_content);
-    ok(!defined $new_contact->{reseller_id}, "check put if reseller_id is undef");
-    ok(!exists $new_contact->{_links}->{'ngcp:resellers'}, "check put absence of ngcp:resellers relation");
-
-    # check if a contact with reseller has resellers link
+    # check if a system contact with reseller has no resellers link
     $contact->{reseller_id} = 1;
     $req->content(JSON::to_json($contact));
     $res = $ua->request($req);
     ok($res->code == 200, "check put successful");
     $new_contact = JSON::from_json($res->decoded_content);
-    ok(defined $new_contact->{reseller_id} && $new_contact->{reseller_id} == 1, "check put if reseller_id is set");
-    ok(exists $new_contact->{_links}->{'ngcp:resellers'} && ref $new_contact->{_links}->{'ngcp:resellers'} eq "HASH", "check put presence of ngcp:resellers relation");
-    ok($new_contact->{_links}->{'ngcp:resellers'}->{href} eq "/api/resellers/1", "check put correct ngcp:resellers relation href");
+    ok(!exists $new_contact->{reseller_id}, "check put if reseller_id is absent");
+    ok(!exists $new_contact->{_links}->{'ngcp:resellers'}, "check put absence of ngcp:resellers relation");
 }
 
 # DELETE
@@ -244,9 +215,6 @@ my @allcontacts = ();
         $res = $ua->request($req);
         ok($res->code == 204, "check delete of contact");
     }
-    $req = HTTP::Request->new('DELETE', $uri.'/api/contacts/1');
-    $res = $ua->request($req);
-    ok($res->code == 423, "check delete of used contact");
 }
 
 done_testing;