title: Notifications are working on an emulator but not on a real device
body: <p>im trying to test my app on a Samsung Galaxy S7(Android 8.0), but the notifications do not appear, i have checked app permissions and battery settings, what ele it could be?</p>
  
  <pre><code>public void sendNotification(View view)
  {
  
      @SuppressWarnings("deprecation")
      NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this);
  
      //creating the intent that’ll fire when the user taps the notification
      Intent intent = new Intent(getApplicationContext(), ViewActivity.class);
      PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, 0);
      mBuilder.setContentIntent(pendingIntent);
      //making notification disappear after being clicked
      mBuilder.setAutoCancel(true);
  
      mBuilder.setSmallIcon(R.drawable.notification_icon);
      mBuilder.setContentTitle("TI connect");
      mBuilder.setContentText("New report has been added!  Total reports: " + repNo);
      mBuilder.setPriority(Notification.PRIORITY_MAX);
  
      NotificationManager mNotificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
  
      mNotificationManager.notify(001, mBuilder.build());
  }
  </code></pre>