Azure login blocked - Error Code: 399287

Dear Support team,

I am an IT Manager working for a global gaming company. We have several legacy portals where I have my company cellphone added as a 2FA. I don't use the App because there are different accounts on all of these old legacy Azure tenants so it would only add extra layers of confusion to keep track of separate apps as well.

The issue started happening today. I was able to sign in to the first two tenants but when I attempted to login to the third one I was now blocked. I am the only admin available as we've gone through many redundancies and I am the only one still in the org for these old legacy portals.

So, no additional Global admins available.

Error details:

Error Code: 399287

Request Id: b7fcf637-adf3-4b1f-8f24-185a98400500

Correlation Id: 019dd490-475a-75b8-9a17-46c4e46ab893

Timestamp: 2026-04-28T14:49:00Z

Verification Method Attempted: Phone number

I have already tried alternative login methods and password reset options but have been unable to complete the identity verification process. I would appreciate your assistance in resolving this issue as soon as possible. Please let me know if any additional information is required.

Best regards,

Ken