Problem:

Teams signs in with your @medschl.cam.ac.uk address, and shows the message "You're missing out! Ask your admin to enable Microsoft Teams for the Clinical School Computing Service":

Solution:

Click the "Use a different account" button, and sign in with your @cam.ac.uk address instead.

The Clinical School Computing Service (CSCS) has disabled Teams on our tenancy to avoid confusion, as it is not in use by staff or students - everyone should have & be using their <crsid>@cam.ac.uk account to sign in to Teams.