Firebase/Android - Regularly Losing Database Connection

I followed the docs for Firebase Auth and Database. Everything works fine after a fresh install: The user can register or log in, the data is retrieved like it should, written like

Solution 1:

It sounds like you may be experiencing a known problem caused with auth token refresh failure discussed here. Try enabling debug level logging using FirebaseDatabase.getInstance().setLogLevel(Logger.Level.DEBUG) and compare the output with the samples included in the discussion linked above. In particular, look for "Error fetching token: An internal error has occured. [ Internal error. ]". If you see that, follow the instructions provided here to fix your google-services.json file.