Manual:  User-Manual-of-Network-Video-Recorder.pdf (wyslink.com)

1. NVR  go to Configuration
It is to select camera, set the motion detection, and set how to action when detect motion
On NVR go to Configuration
->Camera ->Event ->[choose camera] ->Motion Detection
->Linkage Action ->->Check [Notify Surveillance Centre]
-> Click [Apply]

2. Settings on mobile app
->Settings
->Notification
->Enable it
It is let your phone app to accept push notification from recorder.