Firebox Mobile SSL VPN with Azure AD authentication - not working for ONE user
I have setup the Watchguard Mobile SSL VPN to user Azure AD as its authentication. - Following Watchguard documentation - https://www.watchguard.com/help/docs/help-center/en-US/Content/Integration-Guides/General/Azure-firebox-ssl-vpn-active_directory.html
One user cannot connect to the vpn and gets the below errors in the logs. Other users are able to connect fine as intended, a new user created can also connect.
...was rejected, user doesn't exist, check your username msg_id="1100-0005"
....was rejected - Unspecified. Debug
The user is in the correct group to allow access, like all other working users
I've spoken to watchguard support who think its an Azure issue
Has anyone got any ideas on how to resolve this issue?