When entering the authenticator App code, if you are receiving the error 'This code can't be verified' or 'Invalid authentication code', ensure the time on your computer matches the time on your smartphone where your Authenticator App is installed.
To correctly sync the time on the Google Authenticator app:
On your Android device, go to the main menu of the Google Authenticator app then Tap More
Tap Settings then Time correction for codes
Tap Sync now.
On the next screen, the app confirms the time has been synced. You should be able to sign in. The sync will only affect the internal time of your Google Authenticator app, and will not change your device’s Date & Time settings.