If a user has said that they cannot get pass the DUO 2FA page when logging on to something, then follow the steps bellow to understand how to unlock their account.
1. Open DUO Admin. The URL for this is: https://admin-da725da0.duosecurity.com/login?next=%2F
2. Login using your DUO Admin credntials.
3. On the homepage, go to the Locked Out users.
Note: If there are no users that have been locked out, this implies that there is a different issue, but just to be sure use the search bar at the top of the homepage to search the user directly.
4. Find the user you are helping and open their profile.
5. Proceed down the page until you reach what should be four tick boxes (it is three in the example because there were no locked users during the making of this solution).
6. Click on the Active option to unlock the user's account.