It may be caused that you don't open the app to access your phone's permission or the settings is failure for some unknow reason.
Based on the notification, Could you please try the below steps to check if it works?
- Reset the camera and then re-add the camera like the first time did
- Open the APP to access the notification, location, microphone, camera, mobile data from your phone's Settings
- Reset the sound detection and motion detection, then remember to save it
- If you still could not receive the notification, could you use another phone to enter the app and to check if you could receive the notifications.