Why do I get Google Authenticator errors?

This is normally because the time is not synced correctly. To correct this:

Android:

1.        Open Google Authenticator
2.        Tap the three dots in the top right
3.        Select Settings
4.        Tap Time correction for codes

iOS

1.        Open Settings
2.        Select General
3.        Select Date & Time
4.        Toggle Set Automatically so it’s on
5. If it was already on, toggle off then on again