DUO Push fails on iOS 11.3 or higher with the MyWorkDrive mobile app
When accessing the mobile application and performing a DUO push on iOS 11.3 or later, you may not be able to successfully complete authentication if you switch to the Duo Mobile app to approve a Duo Push notification request.
This is a known issue and DUO has published an article on it here.
As an interim workaround, when you receive the Duo Push notification, perform a “force touch” (press hard on the notification and hold) to show the “Approve” and “Deny” actions instead of tapping it to open the Duo Mobile app. You can also drag down on the notification to view these options.
Alternatively, you can enter a passcode or perform phone call authentication to avoid switching into the Duo Mobile app, if your organization’s Duo application policy permits those factors.