If you prefer to register your mobile phone, as opposed to using the Authenticator app, please follow the steps below.

Log into any Microsoft 365 service with your UNOH email address and password. Outlook.com is one example.

Click the I want to set up a different method link, and select Phone.

Select Phone from the drop-down list. Click Next.

Enter your mobile phone number and select Text me a code. Click Next.

Enter the code from the text message you received into the prompt on screen. Click Next

You have successfully registered your phone. Click Next.

Click Done.

Setting up Microsoft Authenticator App

https://support.unoh.edu/articles/microsoft-authenticator-app/