Conditional Access Chromebook Issue

[Shadow_Walker]

Having a very strange issue. Our Chromebooks login to azure through an Azure IDP session. This has been working perfectly for the last year. However we have started to have a problem. In school it works fine as mfa not applied but when staff use chromebooks at at home they get the MFA request, they sign in the login goes through but we get stuck at the sign-in service is hosted by accounts.google.com.mcas.ms and it just hangs there. Seems to be nothing on this anywhere so has anyone had this issue before?