The most common cause for "Incorrect Code" errors is that the time on your device is not synced correctly. To make sure that you have the correct time in your Google Authenticator app, follow the instructions for your operating system below.
On Android
Go to the Main Menu on the Google Authenticator app
Select Settings
Select Time correction for codes
Select Sync now
On the next screen, the app will confirm that the time has been synced, and you should now be able to use your verification codes to sign in.
On iOS (Apple iPhone)
Go to the Settings – this will be your phone’s system settings, not the Authenticator app settings.
Select General
Select Date & Time
Enable Set Automatically
If it’s already enabled, disable it, wait a few seconds and re-enable