Change of device

Question

Hello, I had to change my mobile device but for some reason it keeps asking me for the verification code that reaches the other phone but I no longer have that phone, I don't know what to do because if I use the application in my school for verification, please solve me

Answer 1

Hello @Guadalupe Hernandez Lopez,

I understand how frustrating this issue can be.

Based on your description, may I ask if you have any alternative method to sign-in (SMS, email, Authenticator app,...)? If yes, please try sign-in using this alternative method. 

If you don't have any alternative method to sign in, could you confirm if you're the end-user or IT admin in your school?

If you're an end-user, please reach out to your school’s Microsoft 365 administrator and ask them to reset your MFA settings using the Microsoft Entra Admin Center.

---

If you haven’t yet reached out, here’s a helpful guide to locate your Microsoft 365 administrator: How do I find my Microsoft 365 admin? - Microsoft Support  

Here are some key points to keep in mind:   

You start by contacting the person who originally provided your account, such as a teacher, school administrator, or IT support staff. If unsure who to reach out to, begin with a teacher or staff member you regularly interact with; they can assist or direct you to the right department. Additionally, use your school’s helpdesk portal, support email, or tech support channel for assistance.  

---

 Ask your administrator to follow these steps:    

• Go to Microsoft Entra Admin Center: https://entra.microsoft.com  
• Navigate to Entra ID > Users > All Users.  
• Select your user account.  
• Go to Authentication Methods.  
• Click "Require re-register multifactor authentication".  

This will reset your MFA settings. The next time you sign in, you’ll be prompted to set up the Authenticator app again using a QR code.  

If you're an IT admin, please check to see if there are other IT admins in your organization who can help you with the reset. 

If you are the only administrator in your organization, this request cannot be handled through the Microsoft Q&A forum due to security and privacy limitations. In this case, you will need to contact the Microsoft Data Protection team, as they are the only group authorized and equipped with the necessary tools and verification procedures to confirm your identity and restore administrator access. 

Please try to find the related hotline number to call the frontline and let them raise a ticket for you: Customer service phone numbers - Microsoft Support 

Please carefully follow this instruction to ask for Microsoft Data Protection team support:   

Depending on your country or region. For some countries, when calling the support number, although there are about 30 seconds opening as something "you can visit the link...." But you can ignore this opening and wait until the option, then "1" as a business email user, "1" again for technical help.   

For some countries, it will be an automated conversation like:    

• First, when you call the hotline, it asks what kind of problem you are worried about.   
• Answered: authenticator.   
• A: What kind of product are you using?   
• B: Office 365 for business.   
• A confirmation: education or company account?   
• B: For companies   
• A: Are you an administrator?   
• B: Yes.   
• A: Do you have the other admin in your organization?   
• B: No.   
• A: You need one.... Service request?   
• B: Yes   

If your organization's subscription is from a partner or reseller, contact the reseller's support provider to help open a service request on behalf of you instead.   

Please understand that forum moderators have no control over user accounts, especially when it comes to logging in to your account, resetting your password, changing your access, etc.   

I hope you can successfully revoke your access. If you encounter any difficulties, please feel free to let me know. Thank you and I wish you a great day!  

---

If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment". 

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

Answer 2

Because the previous phone is still registered for multifactor authentication (MFA), the account keeps asking for a code sent to that device. Use one of these options depending on what is available on the school account:

1. Try an alternative sign-in method (if configured)
   • Sign in as usual with username and password.
   • On the MFA prompt, look for “Sign in another way”.
   • Select another method (for example, office phone, SMS, or email) and complete verification.
2. If an alternative method works, update MFA to the new phone
   • After signing in, go to the Security info / Additional security verification page (for work or school accounts this is typically reached via View account → Update info).
   • Delete the old phone from Security info.
   • Add the new phone as a Phone method and/or reconfigure the Microsoft Authenticator app on the new device, following the steps in the MFA setup instructions.
3. If no alternative method works or you cannot get past MFA
   • Contact the school’s IT help desk or Microsoft 365/Entra administrator and ask them to clear or reset your MFA settings.
   • After they reset MFA, the next time signing in, the system will prompt to register MFA again on the new phone (Authenticator app, SMS, etc.).

If the device was lost or stolen, also inform the school help desk so they can update security settings for the account.

---

References:

• Use a screen reader to set up and troubleshoot multifactor authentication
• Common problems with two-step verification for a work or school account
• Frequently asked questions about Microsoft Entra multifactor authentication