New phone - Authenticator will not work

Dear @Michele B,

Thank you for reaching out, and I’m truly sorry to hear that you’re having trouble setting up Microsoft Authenticator on your new iPhone. I understand how frustrating this can be especially when it is blocking your access to your school account. I’ll do my best to help you resolve this as quickly as possible.

To better understand the issue and avoid asking you to repeat any steps you’ve already completed, could you please let me know which troubleshooting steps you have already tried?

In this case, if you are using a school account, I would recommend you contact your IT Admin to reset your MFA settings through the Microsoft Entra Admin Center. Ask your administrator to follow these steps:   

1. Sign in to the entra.microsoft.com as at least one Authentication Administrator. 
2. Select User > All user.  Select the user (your account) to act on and select Authentication methods then select Require re-register of multi-factor authentication.  

Require re-register MFA: This disables all previous authentication methods. You'll then be prompted to configure a new MFA authentication method the next time you try to sign in, so you can set up from the start and add a new authenticator app.  

For step-by-step details, see the official Microsoft documentation: Manage authentication methods for Microsoft Entra multi-factor authentication - Microsoft Entra ID | Microsoft Learn    

If you’re unsure who the Global Admin is within your school account's organization, you can find guidance on locating them here: How do I find my Microsoft 365 admin? - Microsoft Support  

Note: Once re-registration is triggered, all your existing MFA methods such as phone numbers, Authenticator app, or other verification options will be removed. You will need to set up new MFA methods during your next login. Please ensure you have access to a valid phone number or the Microsoft Authenticator app before attempting to sign in again. 

I appreciate your patience, and I am here to help. Looking forward to your response!

Hope you have a great day!

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