Hi there,
As mentioned in earlier topics, the emulator is an old version of Android that does not support Firebase.
From @SteveJG,
Firebase is not usable with the emulator that downloads with aiStarter.
The Android version it emulates is too low. Either use a real device to test your Project or use an advanced emulator that emulates higher Android versions (5 or above should work)
See this topic.
Hope this works.