Global Admin Account Locked Out Due to MFA Issue

Hello,

I am currently locked out of my Microsoft 365 tenant because multi-factor authentication is enforced, and I am unable to complete the verification process due to the error mentioned below and I am the only global administrator for this tenant, which means I cannot access my account or the tenant:

Error message details:

Error Code: 500121

Request Id: 321e431d-8892-400a-b214-45c2b5714400

Correlation Id: 4812fa2a-9d02-e006-a928-89cccf2ae8d0

Timestamp: 2026-02-25T06:32:45Z

Screenshot from authenticator app: I am not able to add the account again as it puts me in an MFA loop

I need assistance regaining access to my administrator account. Please advise on resetting MFA or providing an alternative verification method.I can verify domain ownership if required or provide any required documentation or verification to support the recovery process.

I have tried to log a support case (SR‑1029463817) via phone but have not heard back, I would really appreciate your urgent support. Thank you!