I had Duo Mobile set up on my smartphone already, but it is no longer working. What can I do?

A knowledge base article about I had Duo Mobile set up on my smartphone already, but it is no longer working. What can I do? provided by the UC Berkeley IT Service Hub - Knowledge Portal

In order to fix this issue, please re-enroll your device. Ensure you have backup passcodes ready, and then delete the Duo application from your phone. Reinstall it as a new device — instructions can be found in our 2-Step guide: How to Get Started with 2-Step (KB0011939).