java.lang.RuntimeException: An error occurred while executing doInBackground()
	at android.os.AsyncTask$3.done(AsyncTask.java:325)
	at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:354)
	at java.util.concurrent.FutureTask.setException(FutureTask.java:223)
	at java.util.concurrent.FutureTask.run(FutureTask.java:242)
	at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:243)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
	at java.lang.Thread.run(Thread.java:760)
Caused by: java.lang.IllegalStateException: Default FirebaseApp is not initialized in this process com.hellohasan.chitchatclient:remote. Make sure to call FirebaseApp.initializeApp(Context) first.
	at com.google.firebase.FirebaseApp.getInstance(com.google.firebase:firebase-common@@17.0.0:234)
	at com.google.firebase.iid.FirebaseInstanceId.getInstance(Unknown Source)
	at com.sinch.android.rtc.internal.client.fcm.FcmTask.doInBackground(Unknown Source)
	at com.sinch.android.rtc.internal.client.fcm.FcmTask.doInBackground(Unknown Source)
	at android.os.AsyncTask$2.call(AsyncTask.java:305)
	at java.util.concurrent.FutureTask.run(FutureTask.java:237)
	... 4 more