Anyconnect DOT1x network change after laptop has been locked for a while

Has any one come across this issue?

We have deployed EAP-FAST using Anyconnect NAM as a supplicant. On the supplicant there is a dot1x network configured and a normal wired network configured for when the users take the laptop out of the office.

When the laptops are put into locked mode for about an hour then logged back into, Anyconnect will change the network from DOT1x to Wired and the users lose network access as the switch requires authentication.

The laptops are not sleeping and the users are authenticated and the laptops working before being locked.

Once the laptops are unlocked Anyconnect NAM doesn't even try the DOT1X configuration, it just attempts Wired and will then sit there showing "Limited or no connectivity"