I'm trying to create a new Entra ID tenant on an existing Azure Account. I successfully created the new tenant, but when I try to switch to it, I just get a Portal MFA Enforcement page that says it will redirect me, but never does. Clicking the button to explicitly redirect also doesn't work. I do have MFA setup on the account in the previous tenant and it works for accessing that one.

Has anyone ever seen anything like that before? I've opened a ticket with Microsoft and googled, but couldn't find anyone having a similar issue.