DUO mobile is giving an invalid code.
I have a user who has an iPhone with iOS 8.1.1 (I don't suspect this is the cause; many people have different iOS using DUO)
DUO mobile is on this device and is activated to provide 6 digit code for VPN access.
Domain username and password is not the issue since they are able to log in and out of resources.
The only way to access the VPN is to use a DUO Bypass Token or Bypass their account indefinitely.
This is the second time this has happened. The first time happened a couple of months ago and has been reinstalled and reactivated since then. It seems to be reoccurring.
In my administrative DUO management console, when this user logs in using the bypass token, it doesn't show an IP address from the accessed location. It only shows 0.0.0.0 similar when user's fail their attempts to login.
Please, I am in need of some insight on how to resolve this issue.