Then the app must have been corrupted or has been removed from the target device. Followings are the reason:
- The target device must have updated the OS Version
- The target device must have rest the device/ Factory Restored
- Anti-virus or Security app must have removed or deactivated the app
Solution: For that you need to re-install the app again in the target device. Consult your customer support officer for the assistance with this issue.