Since you’re part of an Enterprise tenant, there should be more than one Global Admin that can reset your Authentication methods. Or any users in general, even secondary accounts you might have (it doesn't have to be a GA), all they need to do is add a current Email address or phone number to your user's Authentication methods. If you don’t have any other users in your tenant, you can try removing the Authenticator app from the MyApps portal, since you should be able to authenticate via Text Message, or even email. If you have other users you can just authenticate via text when they change your number.
You can also try using SSPR if it's enabled, but if not you’ll have to talk to the Azure Data Protection team 866-807-5850.
If you select "I don't have any of these" the sign-in prompt takes you through recovery steps and asks for
- Recovery Codes
- It'll let you update your Security Info with an email or phone, which will unblock your MyApps account in 30 days
Once the MyApps account is unblocked after the 30 day period, you can just remove the Authenticator app/Re-add it, and you can add you email to prevent this from happening again.
Please let me know if this works.
If this answer helped you please mark it as "Verified" so other users may reference it.
Thank you,
James