Link crash

Build version: 1.7.1
Build date: 1981-01-01 01:01:02
Current date: 2021-09-24 09:20:21
Device: Xiaomi Redmi Note 9S
OS version: Android 11 (SDK 30)

Stack trace:
java.lang.NullPointerException
    at java.util.concurrent.ConcurrentHashMap.putVal(ConcurrentHashMap.java:1019)
    at java.util.concurrent.ConcurrentHashMap.put(ConcurrentHashMap.java:1014)
    at com.civix.link.Libraries.JanusWithGoogle.meet.MeetingService.subscribe(MeetingService.java:119)
    at com.civix.link.Libraries.JanusWithGoogle.meet.MeetingClient.subscribe(MeetingClient.java:116)
    at com.civix.link.Screen.CallScreen.subscriberToUser(CallScreen.kt:1719)
    at com.civix.link.Screen.CallScreen$getMediaList$1.onSuccess(CallScreen.kt:1132)
    at com.civix.link.Network.ApiHelper$getData$1.onResponse(ApiHelper.kt:98)
    at com.androidnetworking.common.ANRequest.deliverSuccessResponse(ANRequest.java:727)
    at com.androidnetworking.common.ANRequest.access$6500(ANRequest.java:80)
    at com.androidnetworking.common.ANRequest$6.run(ANRequest.java:709)
    at android.os.Handler.handleCallback(Handler.java:938)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:236)
    at android.app.ActivityThread.main(ActivityThread.java:7861)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:600)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:967)

User actions:
2021-09-24 09:00:03: SplashScreen created
2021-09-24 09:00:03: SplashScreen resumed
2021-09-24 09:00:04: SplashScreen paused
2021-09-24 09:00:04: HomeScreen created
2021-09-24 09:00:05: HomeScreen resumed
2021-09-24 09:00:05: HomeScreen paused
2021-09-24 09:00:05: HomeScreen resumed
2021-09-24 09:00:06: SplashScreen destroyed
2021-09-24 09:00:08: HomeScreen paused
2021-09-24 09:00:08: ChatScreen created
2021-09-24 09:00:08: ChatScreen resumed
2021-09-24 09:00:10: ChatScreen paused
2021-09-24 09:00:10: ChatScreen resumed
2021-09-24 09:00:13: ChatScreen paused
2021-09-24 09:00:13: CallScreen created
2021-09-24 09:00:13: CallScreen resumed
2021-09-24 09:00:14: CallScreen paused
2021-09-24 09:00:14: CallScreen resumed
2021-09-24 09:00:51: CallScreen paused
2021-09-24 09:00:51: ChatScreen resumed
2021-09-24 09:00:58: ChatScreen paused
2021-09-24 09:00:58: ScheduleDetailScreen created
2021-09-24 09:00:58: ScheduleDetailScreen resumed
2021-09-24 09:01:00: ScheduleDetailScreen paused
2021-09-24 09:01:00: ChatScreen resumed
2021-09-24 09:01:01: ScheduleDetailScreen destroyed
2021-09-24 09:01:45: CallScreen destroyed
2021-09-24 09:01:48: ChatScreen paused
2021-09-24 09:01:48: ChatScreen resumed
2021-09-24 09:01:51: ChatScreen paused
2021-09-24 09:01:51: CallScreen created
2021-09-24 09:01:51: CallScreen resumed
2021-09-24 09:01:52: CallScreen paused
2021-09-24 09:01:52: CallScreen resumed
2021-09-24 09:03:45: CallScreen paused
2021-09-24 09:03:45: ChatScreen resumed
2021-09-24 09:03:48: ChatScreen paused
2021-09-24 09:03:48: CallScreen resumed
2021-09-24 09:08:36: CallScreen paused
2021-09-24 09:08:42: ChatScreen resumed
2021-09-24 09:08:45: ChatScreen paused
2021-09-24 09:08:45: CallScreen resumed
2021-09-24 09:12:50: CallScreen paused
2021-09-24 09:12:50: ChatScreen resumed
2021-09-24 09:12:55: ChatScreen paused
2021-09-24 09:12:55: CallScreen resumed
2021-09-24 09:17:31: CallScreen paused
2021-09-24 09:17:31: ChatScreen resumed
2021-09-24 09:17:47: ChatScreen paused
2021-09-24 09:17:47: BoardScreen created
2021-09-24 09:17:47: BoardScreen resumed
2021-09-24 09:17:50: BoardScreen paused
2021-09-24 09:17:50: ChatScreen resumed
2021-09-24 09:17:51: BoardScreen destroyed
2021-09-24 09:18:11: ChatScreen paused
2021-09-24 09:18:11: CallScreen resumed
2021-09-24 09:19:49: CallScreen paused
2021-09-24 09:19:49: ChatScreen resumed
2021-09-24 09:19:51: CallScreen destroyed
2021-09-24 09:20:15: ChatScreen paused
2021-09-24 09:20:15: ChatScreen resumed
2021-09-24 09:20:17: ChatScreen paused
2021-09-24 09:20:17: CallScreen created
2021-09-24 09:20:17: CallScreen resumed
2021-09-24 09:20:20: CallScreen paused
2021-09-24 09:20:20: CallScreen resumed