How to Solve App Center Error? - "Default FirebaseApp is not initialized"

Hi Everyone,

My Xamarin.Android App runs just fine in the emulator but recently has just started to crash when a user runs it on an actual Android Device.
This Error is displayed in App Center:

FirebaseInstanceId.get_Instance ()
**Java.Lang.IllegalStateException: Default FirebaseApp is not initialized in this process "NameOfApp". Make sure to call FirebaseApp.initializeApp(Context) first.**

Some users suggested to edit my OnCreate method within my MainActivty.cs File by adding this snippet of code:
Firebase.FirebaseApp.InitializeApp(this);

I've done this but I do not want to roll out another broken app. can you please let me know if this is the correct way to fix this error or if there are any other ways to do so.

Thanks for your time!