Unable to sign into Azure using personal Microsoft account

I had previously created an Azure subscription using my personal Microsoft account. I have not used it for anything in a while. When I tried to sign back in with it, I'm getting MFA errors. I can sign into other Microsoft services with no issue using MFA in the Authenticator app.

Signing into Azure, I get either this error:
Error Code: 500121
Request Id: 705585c8-146a-4511-8a52-af4e28810b00
Correlation Id: 01a17840-ac54-7506-990f-f69fa6d25c4d
Timestamp: 2026-10-26T12:52:21Z

Or this error:
Request Id: 848626f4-0543-4730-b2cc-986bc0ce9b01
Correlation Id: 3be2f52d-a477-482a-866f-88c2898e68aa
Timestamp: 2026-10-26T11:30:59Z
Message: AADSTS500200: User account '******@natecory.com' is a personal Microsoft account. Personal Microsoft accounts are not supported for this application unless explicitly invited to an organization. Try signing out and signing back in with an organizational account.

From reading different community questions, it sounds like I may be locked out of the only administrator account in my Azure tenant? Can anyone help with this?

Thank you!