Alaram manager not working when app is killed

Question

boolean alarm = (PendingIntent.getBroadcast(this, 0, new Intent("ALARM"), PendingIntent.FLAG_NO_CREATE) == null);

if (alarm) {
    Intent itAlarm = new Intent("ALARM");
    PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 0, itAlarm, 0);
    Calendar calendar = Calendar.getInstance();
    calendar.setTimeInMillis(System.currentTimeMillis());
    calendar.add(Calendar.SECOND, 3);
    AlarmManager alarme = (AlarmManager) getSystemService(ALARM_SERVICE);
 int interval = 60000;
    alarme.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(), interval, pendingIntent);
}else {
    Intent alarmIntent = new Intent(MainActivity.this, BroadcastManager.class);
    alarmIntent.setAction(Intent.ACTION_MAIN);
    alarmIntent.addCategory(Intent.CATEGORY_LAUNCHER);
    PendingIntent pendingIntent = PendingIntent.getBroadcast(MainActivity.this, 0, alarmIntent, 0);

    AlarmManager manager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
 int interval = 60000;

    manager.setInexactRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(), interval, pendingIntent);
}

br = new BroadcastManager();
IntentFilter filter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);
filter.addAction(Intent.ACTION_AIRPLANE_MODE_CHANGED);
this.registerReceiver(br, filter);