Multi Factor Authentication - Change your default security info method

If you want the authenticator app to be the default method used when you sign-in to your work or school account using two-factor verification or for password reset requests, you can set it from the Security info page.

Note: If your default sign-in method is a text or call to your phone number, then the SMS code or voice call is sent automatically during multifactor authentication. As of June 2021, some apps will ask users to choose Text or Call first. This option prevents sending too many security codes for different apps. If your default sign-in method is the Microsoft Authenticator app (which Microsoft recommends), then the app notification is sent automatically.

To change your default security info method

On the Security info page, select Change next to the Default sign-in method information.
Choose Microsoft Authenticator - notification from the list of available methods. If you're not using the Microsoft Authenticator app, select the Authenticator app or hardware token option.
Select Confirm. The default method used for sign-in changes to the Microsoft Authenticator app.