Adding Another Device
It is highly recommended that you setup at least two methods of Duo authentication to your account. You have three options.
Landline: A landline can be your office phone or your home phone.
U2F Device: Universal 2nd Factor is a USB device that is supported only by Chrome.
Passcodes: It is recommended that users get a list of one-time use Passcodes, to allow them to login if their registered device(s) are not available. Follow these instructions to have Duo text you a list of 5 passcodes. Store your codes in a place you can access them if you do not have your phone.