If you have alternate verification methods, when prompted for verification click on Sign in another way.
Otherwise, an admin (or if you happen to have another account with admin privileges) will have to reset your MFA for you; this is done by going to Microsoft 365 admin center > Azure Active Directory > Users > All users > Search and select desired user > Authentication methods and from here you can either click Require re-register multifactor authentication or under Authentication contact info directly change/provide a phone number and/or email address, then click Save.
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