If you’re getting a “Verification not valid” error, it might mean that your authenticator app is not properly synchronized with your device time/network time. To fix this, just go to your device’s Date & Time settings and enable network syncing.
For Android devices, go to your “Date and Time Settings”. Because of several different versions of Android, yours may appear different. Generally, it should be located in:
System > Date & Time
On Android, this is the "Automatic" option:
You’ll see a setting there for Automatic Date and Time and Automatic Time Zone. Make sure both of these are switched “ON”.
On iOS, this is the "Set Automatically" option:
Settings > General > Date & Time
If you still get an error, try deleting the Google Authenticator entry and creating a new entry by re-scanning the QR or re-entering the manual key.
If you still cannot enable or need any help with completing the steps above, please get in touch with us at firstname.lastname@example.org.