I've created a game services app to connect to my app currently set up to run in the internal test track for testing.
However I'm getting a SIGN_IN_FAILED error, from googling it looks like this is related to mismatched values, I've checked:
1) The app id is included in the manifest com.google.android.gms.games.APP_ID
2) The app is uploaded and available for testing under the 'internal test track'
3) The game services account I'm testing with is added to testers
4) The game service app is published (though documentation implies this isn't necessary)
This looks to be everything but it's still not working with that error, so just wanted to know what might be missing or if because it's in internal test track it simply doesn't work unless published to Alpha/Beta?