Through the Duo app, you can generate an authentication passcode even if you are not connected to the internet
You can test this functionality by switching your mobile device into airplane mode.
On your mobile device, launch the Duo app and tap Show in the Charlotte section - a 6 digit number will be visible
Double click "Content by Label" below. Under "Labels*" in the left menu, type all labels relevant to this page (those you have added to the page by clicking the "Labels" icon in the bottom left). When finished, delete this comment!