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Hello @Carline van den Dool
I would like to clarify that we are not Microsoft support; this is a user-to-user support forum. Moderators do not have access to internal systems and cannot intervene directly in Microsoft products. We only offer technical guidance and best practice recommendations based on reported issues. Although I cannot directly assist you, I can show you the steps how to contact Microsoft support.
Are you a normal user or IT admin? If you are a normal user, you can ask the admin to reset your MFA method by following this article: Manage authentication methods for Microsoft Entra multi-factor authentication - Microsoft Entra ID...
If there is no other global administrator, you will need to contact the Data Protection team. They will be able to help you regain access to your tenant.
In this situation, there are two official paths you can take to regain access to the tenant:
1/Go to the following page and contact us at the phone number listed at: Customer service phone numbers – Microsoft Support
As far as I know, you'll need to go through the initial AI system to speak to the human support team. You can refer to the guide below for tips on how to get through this step more easily:

2/If method 1 doesn't work, please go to 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'll be able to go to the Microsoft 365 Admin Center to open a ticket.
Assuming you've already created an account after registering the free trial, you can go to the "Microsoft 365 Admin Center" and click on the Help & Support icon to open the ticket. The agent can create a ticket for the affected tenant and then transfer it to the Data Protection team, who can help them regain access.

Please mention that you are opening the ticket on behalf of the affected tenant to which you do not have access. The support team will help you create the ticket for the affected tenant, and then the Microsoft Data Protection team will provide assistance.
Note: This process will take longer than usual (7-14 business days) for you to regain access to your account, as the Data Protection team is often overwhelmed with the volume of tickets. As a forum moderator, I don't have access to Microsoft's internal systems to help or speed up this process.
On the other hand, if you create the trial account and it resolves the issue, remember to cancel the subscription later to avoid being charged.
Once you regain access to your account, you can use this article to end the subscription: Cancel your Microsoft business subscription in the Microsoft 365 admin center | Microsoft Learn
I hope this information is useful. Please keep me posted once the issue is resolved.
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