need help logging back in microsoft teams and authenticator

Hi @KALISTA RAHIL ANJALI, 

Thank you for posting your question in the Microsoft Q&A forum. I’ve reviewed your description carefully, and it looks like you’re experiencing a circular authentication dependency, a known issue that can occur when changing phones, where both Teams and the Authenticator app require each other to verify your identity. 

In this situation, the best course of action is to contact your school’s IT administrator. They have the necessary permissions and tools to reset your multi-factor authentication (MFA) settings, which will allow you to sign in again. Please kindly ask your administrator to follow the steps in this guide to revoke existing MFA sessions and require re-registration: Manage authentication methods for Microsoft Entra multifactor authentication - Microsoft Entra ID |…   

This process will remove previous sign-in sessions, and the next time you sign in, you’ll be prompted to set up MFA again, which should help you receive the code successfully. 

If you’re unsure who your Microsoft 365 admin is, you can refer to this article: How do I find my Microsoft 365 admin? - Microsoft Support   

Please understand that as a forum moderator, I don’t have the ability to manage authentication settings or reset MFA on your account. Since your account is administered by your school, only your IT department or administrator has the necessary permissions and tools to perform these steps securely. 

I hope this guidance helps you take the right action to resolve the issue and get back to submitting your assignments smoothly. 

Thank you for your time and understanding! 

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