Push notification sometime fails

Ionic Framework ionic-v3
1

Hi freinds

       I am using push notification for both android and ios.
       sometimes I am not getting push notification on either ios or android.
      Can anyone tell me how to debug this?
      Here is my code for sending push...

      ios":{
            "sound":"ping.aiff",
            "priority": 10,
            "contentAvailable": true
     },
      "android":{
            "collapseKey":"zancompute",
             "delayWhileIdle":true,
             "priority":"high"
      }

 Do I need change anything from above code?