Hi @Greater Baltimore Beekeepers,
Thank you for your response. I understand the issue you are currently experiencing.
By design, when you create a Microsoft 365 Business account, Microsoft requires you to complete the Multi-Factor Authentication (MFA) setup process. This requirement is in place to ensure the highest level of security for your account.
The 500121 error commonly occurs when the MFA setup process has not been fully completed.
In this case, you will need to contact Microsoft’s Data Protection team for assistance with resetting and reconfiguring MFA for your account.
Important Note
On this forum, moderators can only provide basic troubleshooting guidance and direct you to the appropriate Microsoft support channels. Moderators are not able to directly assist with the following actions:
- Restoring account access or resetting MFA
- Modifying account-related settings
These actions can only be performed by Microsoft’s Data Protection team.
How to Contact the Data Protection Team
Please look up the Microsoft support phone number for your region and call frontline support. After that, request them to create a ticket for you through the following link:
Customer service phone numbers – Microsoft Support

IVR (Interactive Voice Response) Guidance
To help your call go more smoothly, please refer to the following tips:
- When you call the support line, you may hear an introduction lasting around 30 seconds (for example: “You can visit the link…”). You can skip this and wait for the system to present the options.
- Then:
- Press “1” – if you are a business email user
- Press “1” again – to select Technical Support
In some regions, the system may be fully automated. You can prepare the following sample answers in advance:
- What issue are you experiencing? → Authenticator
- Which product are you using? → Office 365 for Business
- Is this an education or business account? → Business
- Are you an administrator? → Yes
- Are there any other administrators in your organization? → No, I am the only admin
- Do you need to create a service request? → Yes. I need to create a ticket. Please transfer me directly to the Data Protection Team.
Providing this information will help the Data Protection Team verify your identity and assist you in restoring account access and canceling the subscription securely.
Temporary Workaround If You Cannot Reach Phone Support
If you are still unable to contact Microsoft by phone, you may consider the following temporary option:
- Create a new Microsoft 365 tenant (trial version) using the link below: Microsoft 365 Business Plans and Pricing | Microsoft 365

- After the new tenant is created, sign in to the Admin Center, create a support ticket, and request assistance from the Billing Team on behalf of your original locked tenant.

When creating the ticket, it is recommended to use the following subject line to help expedite the request:
Need to contact Data Protection team

Important Notes
- This trial tenant will not have access to any data or settings from your original tenant. It is used only as a temporary method to contact Microsoft Support.
- Please prepare the necessary information to verify your identity and administrative ownership of the locked tenant.
- Resolution may take longer since you are contacting support from a different tenant.
- Do not forget to cancel the trial subscription once the issue with your original account has been resolved, to avoid any unintended charges.
I hope the information above is helpful. Please follow the steps provided and let me know the outcome. If the issue is not resolved, we can continue working together to find the most suitable solution.
Thank you for your patience and understanding. If you have any additional questions or concerns, please feel free to share them in the comments so I can continue assisting you.
I look forward to continuing our discussion.
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