I did not receive the converted files - what should I do?

In order to solve this issue, the following steps should be performed: 

- Close app completely (including from multitasking window, by double pressing home button and swiping the app up), but do not uninstall app.
- Go to the Settings app.
- Navigate to Notification Center.
- Scroll down to find app and tap on it
- Enable all notifications for it.
- Then just start app again.