If your Two Factor Authentication (2FA) code does not work:
Try synchronising the time in the Google Authenticator App settings. This could already solve the problem.
If you've lost access to your mobile phone or accidentally deleted the authenticator app:
In those cases you need to reset your 2FA.
You can reset your 2FA yourself if you have written down or saved the backup code provided when setting up your 2FA.
If your backup code has been lost, we need to reset your 2FA for you: