Can't log in to Entra ID from Partner Center

I sell apps in the Microsoft Store and have an Entra ID. I'm the one and only user of that Entra ID.

I rarely need to log into my Entra ID--I log in every two years to generate a new application key for a Store API app that pulls app sale data. So it's been a long time since my last login. For the past few weeks, I've tried to log in--I could log into Partner Center with my Microsoft Account. But when I go to manage users and am asked to login with my Entra ID, I log in, and am prompted to verify. I select the Text option (and the partial number looks correct), and I get the message “Sorry, we’re having trouble verifying your account. Please try again.”

I've opened case 2507210040008554 but there hasn't been any movement and I can't even pull it up in partner center (the page shows an error accessing the information).

I'm in a Catch-22. I can't verify by Text, and I can't verify using the Authenticator app or entering a code--this Entra ID isn't in my Authenticator, and when I try to add it to Authenticator, it wants me to use Authenticator to enter or select codes WHILE I'M AREADY IN AUTHENTICATOR. I'm stuck.

Please help. @Raja Pothuraju