Can sign into Microsoft servers. Cannot sign into xbox servers

I can sign into my Microsoft account successfully and remain signed in.

However, when I select my Xbox profile, Xbox tells me I need to sign in. My Microsoft credentials are accepted, but Xbox immediately signs me out again.

I have reproduced this with three different Microsoft/Xbox accounts, on my phone, PC and Firestick, and using both home broadband and mobile data.

Microsoft account authentication itself is working normally. The failure only occurs when Xbox attempts to load/authenticate the Xbox profile.

Please can this be escalated as an Xbox profile/session authentication issue rather than a password or device issue?

I have also done the sign in helper and changed passwords yet that helper says my account is blocked. But successfully signed into 365. Even through that it jumps me out of signing in when using the xbox profile link.