Some staff use DUO as a secondary user authentication option when logging into the Bethel Portal. DUO is typically an APP added to a phone or computer and triggers a notification at the time of login.
If your enrolled DUO device is currently offline, you can simply use the "DUO Mobile Passcode" option when prompted with DUO Authentication. I've attached some images to show the steps I took on my account. This option comes automatically when you enroll your device with DUO Mobile. You can open the app on your offline device and still select the account you are trying to sign into. In this case, selecting the portal account and submitting the 6-digit code should do the trick.