Microsoft Authenticator App Authentication Code Not Displaying Issue

Disclaimer: I see that you posted this case in the Korean forum (KO-KR), but your question is written in English. Therefore, I will respond in English to keep our conversation consistent. Please let me know if you would prefer to continue in another language.

Hello @TECHWELL

As you described, this issue may have occurred because the Microsoft Authenticator app data was not properly transferred to your new phone.

(It is important to transfer your Authenticator app data before switching to a new device to avoid losing access to your accounts. The Authenticator app stores your verification codes, and without migrating this data in advance, you may be locked out of essential services such as email or work accounts. Transferring the data beforehand ensures your sign‑in methods remain intact and helps prevent recovery issues later.)

May I confirm whether you still have access to the Authenticator app on your old phone? If so, you can also refer to the following thread for guidance on properly transferring the Authenticator app.

How do I transfer my Microsoft Authenticator data from my iPhone to a Samsung phone? - Microsoft Q&A

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If you no longer have access to your old phone and are unable to use other verification methods (such as a phone call, SMS, or email) to sign in to your account, the only way to regain access is to contact your IT Administrator or Global Administrator.

As you are using a work account, they can update your authentication methods, including your phone number, through the Microsoft Entra admin center and help you restore access to your account.

In the Entra admin center, an administrator can set user accounts to require a re-enrollment of multi-factor authentication (MFA). Ask your administrator to follow the steps shown in the following article:

Manage user authentication methods for Microsoft Entra multi-factor authentication

• Sign in to Microsoft Entra - Microsoft Entra admin center
• User -> all users. Select the user you want to act on, and then select "Authentication methods". then select "Require multi-factor authentication re-registration".

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

*Note:

• Please note that in this case, you only need to find the global admin of your organization’s tenant. They are the ones who can help you regain access to your account.
• The global admin is usually someone in your school’s IT team or a system administrator. They manage Microsoft 365 settings, licenses, and security

Take care, and have a great week!

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