Hello @Triana Montserrat ,
Thank you for reaching out to Microsoft QnA forum. There are 3 possible ways you can try to get access back to the accounts on Authenticator App:
- You can restore accounts on authenticator App provided you had backed it up earlier, more details available on Restore account credentials from Microsoft Authenticator.
- If you had registered alternate authentication method like contact number than you can try following:
- Try to login to https://aka.ms/mfasetup.
- Complete MFA with Contact Number (Call or OTP).
- Register Authenticator App again.
- If above both methods do not work, you would need to contact you IT Admin/Global Admin to reset Authentication Methods on your account using steps mentioned on following article for option Require re-register MFA: Manage user authentication options
Hope this will help. Please "Accept the answer" if the information helped you. This will help us and others in the community as well.