If you are having trouble with Gnome Online Accounts not logging into Google make sure you are fully updated and try again. Especially if you are getting the error “Credentials have expired”. If that doesn’t work, then open a terminal and try,
pgrep goa-daemon | xargs kill -9
This will kill the Gnome Online Accounts daemon which will then automatically re-spawn. Worked for me!
What if the Credentials have expired fix doesn’t work?
Of course, if it doesn’t work for you you might have a different problem. I would suggest searching the Gnome Online Accounts mailing list here or asking them in their IRC if you aren’t able to solve it on Google.