Many users haven’t remembered their Gmail password, that reason they don’t use to Gmail account. If you are one of them then you can recover to your password by 2-step verification. In this process you have get verification code by Google. If your Google codes aren’t working then you can resolve to your problem by following steps:
1. Go to the main menu on the Google app
2. Click Settings
3. Click Time correction for codes
4. Click Sync now