Cannot access my account after code from Authenticator App does not work after I change my mobile

If you have changed phones and lost access to Microsoft Authenticator, you’ll need to use Microsoft account recovery process. You cannot disable Authenticator yourself without logging in, but you can escalate to Microsoft Account Recovery or tenant recovery (for business accounts). This requires proving ownership with billing details, subscription IDs, or domain verification. Once verified, Microsoft support can reset your MFA settings.