Question: I'm creating notification system I need to give notification every hour but now it's only giving one for a day

```
protected void onStart() {
        super.onStart();

            Calendar calendar = Calendar.getInstance();

            calendar.set(Calendar.HOUR_OF_DAY, 16);
            calendar.set(Calendar.MINUTE, 30);

            Intent intent = new Intent(getApplicationContext(),NotificationReceiver.class);

            PendingIntent pendingIntent = PendingIntent.getBroadcast(getApplicationContext(),100,intent,PendingIntent.FLAG_UPDATE_CURRENT);

            AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
            alarmManager.setRepeating(AlarmManager.RTC_WAKEUP,calendar.getTimeInMillis(),alarmManager.INTERVAL_DAY,pendingIntent);

        }

```

Answer: 
you are using `alarmManager.INTERVAL_DAY` so it will execute every 24h change it with `alarmManager.INTERVAL_HOUR`
```
     alarmManager. setRepeating  (AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(),  alarmManager.INTERVAL_HOUR,   pendingIntent);

```