Google Authenticator I had no problem using Authenticator for the first month.  Two weeks ago, my phone's operating system upgraded and now Authenticator will not work.  I have uninstalled it, re-downloaded it, and reinstalled.  No matter what function I choose (sync time, setup) I get an error message that Authenticator has stopped working.  Also, since I need the two-factoring for our website, that the codes stopped working on that.  I keep reporting the issue to Google but of course have had no response.  Any suggestions?
If you can't access to Google Authenticator in any way, I suggest trying Duo Mobile or FreOTP Authenticator

I tried Duo Mobile and I personally use it for my personal Google Account. It works like a charm. Feel free to draw feedback if that resolves the question for you.