Old mobile phone broken - no access to Authenticator App

Question

My old phone broke, so I can't get into the Office programs anymore. Everytime, Microsoft wants a code from the Authenticator app. If I say I don't have access to it, I get 2 choices, but both run through the Authenticator app.

Every attempt to get online support is linked to the registration, which I can't do because I can't get into the app anymore.

Can someone please help me?

Thank you