A. Try force quitting the app and reopening it. Double-tap the home button (or swipe up from the bottom of the screen on newer models) to see all open apps, then swipe up on Avaya Workplace to close it. Reopen the app afterward.
B. If the problem persists, try uninstalling and reinstalling the app. Press and hold the app icon until it wiggles, then tap the 'X' to delete it. Go to the App Store, search for Avaya Workplace, and reinstall it.