diff --git a/lib/NGCP/Panel/Form/Subscriber/SubscriberAPI.pm b/lib/NGCP/Panel/Form/Subscriber/SubscriberAPI.pm
index f055b03297..431b90a2cd 100644
--- a/lib/NGCP/Panel/Form/Subscriber/SubscriberAPI.pm
+++ b/lib/NGCP/Panel/Form/Subscriber/SubscriberAPI.pm
@@ -235,6 +235,17 @@ has_block 'actions' => (
     render_list => [qw/save/],
 );
 
+sub validate_timezone {
+    my ($self, $field) = @_;
+    my $c = $self->form->ctx;
+    return unless $c;
+
+    my $value = $field->value;
+    unless (NGCP::Panel::Utils::DateTime::is_valid_timezone_name($value, 0, $c, 1)) {
+        $field->add_error($c->loc('Invalid timezone name: '.$value));
+    }
+}
+
 # override parent here to prevent any password magic
 sub update_fields {
 #IMPORTANT! redefined sub update_fields with no super call disable call of the update_field_list and defaults methods
@@ -254,7 +265,6 @@ sub update_fields {
     return;
 }
 
-
 1;
 
 # vim: set tabstop=4 expandtab:
diff --git a/lib/NGCP/Panel/Form/Subscriber/SubscriberSubAdminAPI.pm b/lib/NGCP/Panel/Form/Subscriber/SubscriberSubAdminAPI.pm
index bc5245e39b..71220bcf23 100644
--- a/lib/NGCP/Panel/Form/Subscriber/SubscriberSubAdminAPI.pm
+++ b/lib/NGCP/Panel/Form/Subscriber/SubscriberSubAdminAPI.pm
@@ -121,11 +121,11 @@ has_field 'status' => (
 );
 
 has_field 'timezone' => (
-    type => '+NGCP::Panel::Field::TimezoneSelect',
+    type => 'Text',
     label => 'Timezone',
     element_attr => {
         rel => ['tooltip'],
-        title => ['The timezone of the subscriber.']
+        title => ['The timezone of the subscriber. See http://search.cpan.org/dist/DateTime-TimeZone/lib/DateTime/TimeZone/Catalog.pm for a full list of valid timezone names.']
     },
 );
 #we need customer_id field in the form to don't delete customer_id from the resource as absent field during form validation
@@ -324,6 +324,17 @@ sub validate_webpassword {
     NGCP::Panel::Utils::Form::validate_password(c => $c, field => $field, utf8 => 0);
 }
 
+sub validate_timezone {
+    my ($self, $field) = @_;
+    my $c = $self->form->ctx;
+    return unless $c;
+
+    my $value = $field->value;
+    unless (NGCP::Panel::Utils::DateTime::is_valid_timezone_name($value, 0, $c, 1)) {
+        $field->add_error($c->loc('Invalid timezone name: '.$value));
+    }
+}
+
 sub update_fields {
 #IMPORTANT! redefined sub update_fields with no super call disable call of the update_field_list and defaults methods
     my ($self) = @_;