How do I activate UCLA Multi-Factor Authentication on a landline?

The following step-by-step instructions detail how to activate UCLA Logon Multi-Factor Authentication (MFA) using the following device: landline.

Using a web browser, visit https://accounts.iam.ucla.edu/mfa.
Log into the application using your UCLA Logon ID and password.
At the "About MFA in UCLA Logon" window, click on the [CONTINUE] button.
At the "Link a Device:" window, select Landline.
At the "Link Landline" window, enter a memorable label for your phone, your landline phone number, and an extension if applicable.
Click the [ACTIVATE WITH PHONE CALL] button.
You will receive a phone call on your landline phone from Duo. Enter the six-digit code you received into the box, then click the [CONTINUE] button.
The Landline you just added should now be listed under Linked Devices:.