If Google Authenticator codes are not working, you can force the app to re-synchronise your time.
To do so, open the Google Authenticator app
Click the menu button (3 vertical dots)
Click Time correction for codes
Click Sync now
You can now try to use your 2FA codes again.
For more information, you can visit the Google help article on 2FA and time sync here: https://support.google.com/accounts/answer/2653433