Please remove and reinstall the app.
Remove Your app
1. On your device, make sure you have exited any apps by tapping the Home button
2. Find your app and press down on the icon until the “x” appears.
3. Tap the “x” to remove the app from your device
Reinstall Your App
4. Tap to open the App Store on your device
5. At the bottom, tap “Updates"
6. At the top, tap “Purchased"
7. Find your app in the list, and tap the cloud download icon