diff --git a/src/api/ngcp-call.js b/src/api/ngcp-call.js
index e828318d..294da75e 100644
--- a/src/api/ngcp-call.js
+++ b/src/api/ngcp-call.js
@@ -107,18 +107,19 @@ export function callConfigure ({ baseWebSocketUrl }) {
     $baseWebSocketUrl = baseWebSocketUrl
 }
 
-export async function callInitialize ({ subscriber }) {
+export async function callInitialize ({ subscriber, instanceId }) {
     $subscriber = subscriber
-    callRegister()
+    callRegister({ instanceId })
 }
 
-export function callRegister () {
+export function callRegister ({ instanceId }) {
     if (!$socket) {
         $socket = callCreateSocket()
         const config = {
             sockets: [$socket],
             uri: getSubscriberUri(),
-            password: $subscriber.password
+            password: $subscriber.password,
+            instance_id: instanceId
         }
         $userAgent = new jssip.UA(config)
         const delegateEvent = (eventName) => {
diff --git a/src/helpers/call-utils.js b/src/helpers/call-utils.js
index f2685004..cafdcdf0 100644
--- a/src/helpers/call-utils.js
+++ b/src/helpers/call-utils.js
@@ -1,3 +1,20 @@
+import { getLocal, setLocal } from 'src/storage'
+import { v4 } from 'uuid'
+
+const SIP_INSTANCE_ID_NAME = 'sip_instance_id'
+
+export function setSipInstanceId (instanceId) {
+    setLocal(SIP_INSTANCE_ID_NAME, instanceId)
+}
+
+export function getSipInstanceId () {
+    let instanceId = getLocal(SIP_INSTANCE_ID_NAME)
+    if (!instanceId) {
+        instanceId = v4()
+        setSipInstanceId(instanceId)
+    }
+    return instanceId
+}
 
 export function callIcon (call) {
     if (call.call_type === 'cfu' || call.call_type === 'cfna' ||
diff --git a/src/store/user.js b/src/store/user.js
index 930c27a0..c7a745ad 100644
--- a/src/store/user.js
+++ b/src/store/user.js
@@ -26,6 +26,7 @@ import {
 import { date } from 'quasar'
 import { callInitialize } from 'src/api/ngcp-call'
 import { setLocal } from 'src/storage'
+import { getSipInstanceId } from 'src/helpers/call-utils'
 
 export default {
     namespaced: true,
@@ -340,7 +341,8 @@ export default {
                     }
                     try {
                         await callInitialize({
-                            subscriber: userData.subscriber
+                            subscriber: userData.subscriber,
+                            instanceId: getSipInstanceId()
                         })
                     } catch (err) {
                         console.log(err)