A cloud-based identity and access management service for securing user authentication and resource access
Please note that this forum is not Microsoft support, this is a user-to-user support forum. Therefore, I cannot directly escalate this for you. However, I can guide you how to contact Data Protection team.
If MFA registration is interrupted during initial tenant setup, the administrator account can become temporarily inaccessible. This may result in errors such as AADSTS5000228 – “Access to tenant is denied”, preventing sign‑in to the Microsoft Entra admin center and Microsoft 365 admin center. In this state, self‑service recovery options are not available.
In this situation, you will need to contact Data Protection team. They can help you regain access to your tenant. I know this may sound a bit ridiculous, but creating another trial tenant to open a support ticket is currently the most direct option available, aside from contacting phone support. If you would like to try with phone support, you can try with the script below: Customer service phone numbers - Microsoft Support
From what I know, you will need to get past the initial AI system to reach the live support team. You can refer to the guide below for tips on how to get through more easily:
If you have tried phone support and it's not working, please follow this link to create a trial tenant: https://www.microsoft.com/en-us/microsoft-365/business/microsoft-365-business-basic?msockid=3eb6980b5c6860e63a588d0c5d1761d6 - after that you will be able to access to Microsoft 365 Admin Center to raise the ticket
Assuming that you have already created an account after registering a free trial and you can go to Microsoft 365 admin center and click "Help & support" icon to raise your ticket.
Please mention that you are raising ticket on behalf of the affected tenant that you do not have access to.
On the other hand, if you do create the trial and it resolves the issue, please remember to cancel the subscription afterward to avoid any related charges.