Changing your login Method Log into https://www.office.com. Authenticator will send you a text or call the device(s) you originally setup. Enter code or take call and authorize login. Click on your name in the top right coroner. Click on View Account. On the right side, select Update Info. This gives you the ability to add or change your contact method. As you can see below, I have 3 phones set up (phone icon) and the Authenticator app. These methods can be deleted, and new ones added. To add, click the +Add sign-in method. If you lost your phone, you could force a sign out of all devices on this same page.