Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Regarding your issue, this happens because two-step verification is still linked to the previous phone, preventing the account from verifying the sign-in request. Since this is a work account, please contact your company’s IT administrator or help desk and ask them to reset your multi-factor authentication (MFA) methods. Once the reset is completed, you can register the new phone for verification. For security reasons, this change must be handled by your organization’s IT team. They can follow these steps:
- Sign in to the entra.microsoft.com as at least Authentication Administrator.
- 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 more details, please refer to: Manage user authentication methods for Microsoft Entra multifactor authentication.
Find Your Microsoft 365 Admin: If you’re unsure who the Global Admin is within your organization, you can find guidance on locating them here: How do I find my Microsoft 365 admin?
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.
Hopefully it will help work with your issue and if you have any other questions or need further assistance, feel free to ask.
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