app crash while logout

[SatyamKr07]

on successful google login, press back button. Now open app again and try to logout. App crashes with the following null pointer exception issue:

I/flutter (30938): [GET] AuthController has been initialized
I/flutter (30938): [GET] ProductController has been initialized
I/flutter (30938): [GET] GetMaterialController has been initialized
I/flutter (30938): [GOING TO ROUTE] /splashscreen
I/flutter (30938): [GOING TO ROUTE] /
I/flutter (30938): [REMOVING ROUTE] /splashscreen
I/flutter (30938): [GOING TO ROUTE] /
I/flutter (30938): [REMOVING ROUTE] /
D/FirebaseAuth(30938): Notifying id token listeners about a sign-out event.
D/FirebaseAuth(30938): Notifying auth state listeners about a sign-out event.
D/AndroidRuntime(30938): Shutting down VM
E/AndroidRuntime(30938): FATAL EXCEPTION: main
E/AndroidRuntime(30938): Process: com.learning.todo_app_getx, PID: 30938
E/AndroidRuntime(30938): java.lang.NullPointerException: Attempt to invoke virtual method 'void c.a.b.a.i.a(java.lang.String, java.lang.Object)' on a null object reference
E/AndroidRuntime(30938): at io.flutter.plugins.firebaseauth.a$c.a(:710)
E/AndroidRuntime(30938): at com.google.firebase.auth.f1.run(:3)
E/AndroidRuntime(30938): at android.os.Handler.handleCallback(Handler.java:873)
E/AndroidRuntime(30938): at android.os.Handler.dispatchMessage(Handler.java:99)
E/AndroidRuntime(30938): at b.b.a.a.d.e.o3.dispatchMessage(:6)
E/AndroidRuntime(30938): at android.os.Looper.loop(Looper.java:232)

Note: on successful google login, if we don't press back button and now logout, we are successfully logged out without app crash.