Teams and autheticator

Dear @Burke, Mike,

Good day! Welcome to Microsoft Q&A forum!

Based on your description, I understand that you’re being repeatedly prompted to sign in to your work account in the Microsoft Teams mobile app. When you attempt to sign in, Teams automatically opens the Microsoft Authenticator app, but instead of approving the request, you’re asked to enter a verification code. Since you’re already in the Authenticator app and don’t see anywhere to enter that code, you’re looking for help completing the sign-in process and resolving the authentication loop.Regarding this situation, In the meantime, kindly try the following suggestions to try to sign in using a one-time passcode (OTP):

• Open Microsoft Teams and start signing in to your work account
• On the sign-in screen, select “Sign in another way” (or “Sign in with a different method”)
• Choose One-time passcode (OTP) as the sign-in option
• Open the Microsoft Authenticator app on your phone > Click on the account that you're trying to sign in
• Find the 6-digit OTP code shown there
• Copy the code and paste or enter it back into Microsoft Teams
• Submit the code to complete the sign-in

If the OTP option does not appear, or if the code is rejected, you might need to reach out to your organization’s IT administrator because they can help reset your MFA registration following this article: Manage user authentication methods for Microsoft Entra multifactor authentication

I hope this information is helpful. Please follow these steps and let me know if it works for you. If not, we can work together to resolve this.

Please understand that our initial response does not always resolve the issue immediately. However, with your help and more detailed information, we can work together to find a solution.

Kindly let me know when there are updates or if you need further assistance. Any updates you’re able to share would be really helpful. I appreciate your time and look forward to hearing how things are going! 

Thank you for your time and patience.

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Teams and Authenticator are putting the sign-in into a loop because the verification method being requested doesn’t match what Authenticator is currently set up to do.

Try these steps on the phone:

1. In the Teams sign-in screen, when it says to approve in Authenticator, look for and tap Other ways to sign in or Sign-in options instead of just following the automatic switch to Authenticator.
2. Choose a different method that you can complete, such as:
   • Send notification (approve a push in Authenticator), or
   • Use a verification code (then, in Authenticator, tap your work account and use the One-time password code if it appears), or
   • SMS/phone call if those are configured.
3. If Teams is asking to “enter a code into Authenticator,” that is the cross‑device flow (you enter a code shown on one device into Authenticator on another). On a single phone this has nowhere to be entered, so switch to a method like Send notification instead.
4. If none of the alternative sign-in methods work or no other method is configured, contact the organization’s IT admin and ask them to reset the account’s MFA/Authenticator registration in Microsoft Entra ID so Authenticator can be set up again from scratch.

If the account is a business/school account and there is no other admin who can reset MFA, the tenant admin must contact Microsoft support (Data Protection team) by phone to have MFA reset, as described in the referenced Q&A threads.

References:

• Sign in using Microsoft Authenticator
• Sign in with a passkey in Microsoft Authenticator
• Why am I having trouble signing in to Microsoft Teams?
• Microsoft authenticator sending me into a spiral - Microsoft Q&A
• Microsoft Authenticator app doesn't show 6-digit OTP code - Microsoft Q&A
• I have a Micrsoft business account and I am the admin and the only user registered under this account. I can't log in because i have replaced my phone and the authenticator doesn't work. - Microsoft Q&A
• Requesting a Tenant Admin MFA Reset - Microsoft Q&A