Android не обнаруживает маяк в фоновом режиме

Я работаю над маяком, используя библиотеку Altbeacon. Я пытаюсь обнаружить маяк в фоновом режиме, как указано здесь. Активность моих приложений отслеживает маяк и правильно возвращает значения. Но когда я убиваю приложение, оно не обнаруживает маяк. Ниже приведен мой класс приложения.

public class BeaconApplication extends Application implements BootstrapNotifier{

private static final String TAG = "BeaconApplication";
private RegionBootstrap regionBootstrap;
private BackgroundPowerSaver backgroundPowerSaver;
private boolean haveDetectedBeaconsSinceBoot = false;
private MainActivity mainActivity = null;

@Override
public void onCreate() {
    super.onCreate();
    BeaconManager beaconManager = org.altbeacon.beacon.BeaconManager.getInstanceForApplication(this);
    beaconManager.getBeaconParsers().add(new BeaconParser().
            setBeaconLayout("m:2-3=0215,i:4-19,i:20-21,i:22-23,p:24-24,d:25-25"));
    beaconManager.setBackgroundScanPeriod(5000l); // 5 secs
    beaconManager.setForegroundScanPeriod(5000l); // 5 secs
    Log.d(TAG, "setting up background monitoring for beacons and power saving");
    Region region = new Region("backgroundRegion",
            Identifier.parse("fda50693-a4e2-4fb1-afcf-c6eb07647825"), Identifier.parse("10004"), Identifier.parse("54480"));
    regionBootstrap = new RegionBootstrap(this, region);

}

@Override
public void didEnterRegion(Region region) {
    Log.d(TAG, "did enter region. UniqueId: "+ region.getId1());
    if (!haveDetectedBeaconsSinceBoot) {
        Log.d(TAG, "auto launching MainActivity");
        sendNotification();

        haveDetectedBeaconsSinceBoot = true;
    } else {
        if (mainActivity != null) {
            mainActivity.logToDisplay("I see a beacon again" );
        } else {
            Log.d(TAG, "Sending notification.");
            sendNotification();
        }


 }

}



@Override
public void didExitRegion(Region region) {
    if (mainActivity != null) {
        mainActivity.logToDisplay("I no longer see a beacon.");
    }
}

@Override
public void didDetermineStateForRegion(int i, Region region) {
    if (mainActivity != null) {
        mainActivity.logToDisplay("I have just switched from seeing/not seeing beacons: " + i);
    }
}

private void sendNotification() {
    NotificationCompat.Builder builder =
            new NotificationCompat.Builder(this)
                    .setContentTitle("Welcome to beacon zone")
                    .setContentText("You are in a beacon zone.")
                    .setSmallIcon(R.mipmap.ic_launcher);

    TaskStackBuilder stackBuilder = TaskStackBuilder.create(this);
    stackBuilder.addNextIntent(new Intent(this, MainActivity.class));
    PendingIntent resultPendingIntent =
            stackBuilder.getPendingIntent(
                    0,
                    PendingIntent.FLAG_UPDATE_CURRENT
            );
    builder.setContentIntent(resultPendingIntent);
    Uri alarmSound = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
    builder.setSound(alarmSound);
    builder.setAutoCancel(true);
    Notification notification = builder.build();
    notification.flags = Notification.DEFAULT_LIGHTS;
    notification.flags = Notification.FLAG_AUTO_CANCEL;
    notification.flags = Notification.FLAG_ONLY_ALERT_ONCE;
    NotificationManager notificationManager =
            (NotificationManager) this.getSystemService(Context.NOTIFICATION_SERVICE);
    notificationManager.notify(1, notification);
}

public void setMonitoringActivity(MainActivity activity) {
    this.mainActivity = activity;
}
}

И вот мой файл манифеста

<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />

<application
    android:name=".BeaconApplication"
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
    <activity
        android:name=".MainActivity"
        android:label="@string/app_name"
        android:theme="@style/AppTheme"
        android:launchMode="singleInstance" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

</application>