If you are locked out of your Microsoft 365 tenant and are the only Global Administrator, you will need to contact Microsoft Support for assistance. Since you mentioned that you opened a ticket but did not receive a solution, it's important to escalate the issue to ensure it is addressed properly.
Here are some steps you can take:
- Contact Microsoft Support Directly: Use the customer service phone numbers for Microsoft Support to speak with a representative. Explain your situation clearly, including your tenant name and the fact that you are the only Global Administrator.
- Provide Necessary Information: When contacting support, be prepared to provide details such as your administrator account email address, the domain name of your tenant, and any error messages you are encountering.
- Request Data Protection Team Assistance: Since you are locked out and have lost access to your MFA device, ask the support representative to escalate your case to the Data Protection Team, which can assist in verifying your identity and restoring access to your account.
- Consider Creating a New Trial Tenant: If you are unable to get immediate help, you might consider setting up a new trial tenant to submit a support request from there, clearly stating that you are locked out of your original tenant.
Remember, it’s crucial to have at least two Global Admin accounts in the future to avoid such lockouts.
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