Hi @Philipp_rf2x
According to your case description, you are stuck in a loop.
It is recommended that you reset your account login method on your personal security information page, and then try to see if you can get out of the loop and complete the login to the Teams admin center.
If this does not work, you need to contact your administrator.
If your tenant has another global administrator, you can ask them to change the Entra ID of your account so that you can re-register for MFA in the authenticator app. To do this, you can ask another global administrator to follow these steps:
- The administrator logs in to the Azure portal and access Azure Active Directory.
- Go to the users blade on the left.
- Click the user account that has been locked out.
- Click Authentication methods, and then click Require re-register multi-factor authentication.
If you are the only global administrator of the account and are completely blocked, you can contact our support team. You can check the following articles to get the support number, depending on your country.
About how to find your organization's administrator, please refer to How do I find my Microsoft 365 admin.
When looking for your Microsoft 365 admin to contact an agent on your behalf, reset your password, delete an account, or do other tasks, here's who you should contact:
Universities and schools: Contact your technical support team. At universities or colleges, usually you can find a link on your university site.
At other schools, there may be just a couple technical people who have admin permissions. Try asking your teacher or school administrators for where you should go to get technical help.
Large businesses: Contact your internal help desk / technical support.
Small businesses: Contact the business owner / co-owner. Often they give admin permissions to their IT consultant who does all the computer maintenance work for their business.
By default, the person who signs up for and buys a Microsoft 365 for business subscription gets admin permissions. That person can assign admin permissions to other people to help them manage Microsoft 365 for their organization.
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