Using teams desktop app with gmail account

[BroganOs]

I have google setup as an external identity on my Azure tenant and have been logging into teams via the web app seamlessly using my test user gmail account. 2 days before a large course is about to start, I noticed that if you log in using the desktop app you are asked to authenticate using a one-time passcode instead and it's not always seemless.

 

I've getting errors where the app continues to log you in without a code, but you get an authorization error when you click on the teams icon on the left hand side. Needless to say the panic has set in!

 

Has anyone else experienced this?