Call not trigger onRinging event on ReactNative

Hello, I’m developing an using React Native and try to integrate the Sendbird Call into my app. I followed this tutorial How to build a React Native video chat app with Sendbird Calls but there’re some issue with Sendbird Call JavaScript SDK undefined is not a function (near '...}).finally(function () {...')] which make it cannot run on React-Native.

So I decide to implement in Native module by using Android and iOS SDK by forking and modifying one library I found and this is my fork jason-supercoder/react-native-sendbird-calls. After implementing to my app and testing, the call never ringing on the callee side.

For example:
User A calls User B → Not ringing
User A calls User B + User B calls User A → now it rings on both sides.

Did I missed something why it doesn’t ring?

Android Logs:

Fatal Exception: java.lang.RuntimeException: Unable to start service with null: java.lang.NullPointerException: Attempt to invoke virtual method 'boolean android.content.Intent.getBooleanExtra(java.lang.String, boolean)' on a null object reference
       at android.os.Handler.dispatchMessage(
       at android.os.Looper.loopOnce(
       at android.os.Looper.loop(
       at java.lang.reflect.Method.invoke(

This issue has been solved by adding FCM Server Key to Sendbird call app notification settings