No se llama a GcmListenerService cuando la aplicación está en segundo plano

No se llama a GcmListenerService cuando la aplicación está en segundo plano o cuando el teléfono está bloqueado o en modo de suspensión, pero se activa la notificación. Cómo se llamará esto cuando la aplicación esté en primer plano, funciona idealmente. El código para GcmListenerService está siguiendo

  public class MyGcmListenerService extends GcmListenerService {

    private static final String TAG = "MyGcmListenerService";
    LocalDataBaseManager mDbManager;
    String message;
    Random randomNumber;
    long ID;
    /**
     * Called when message is received.
     *
     * @param from SenderID of the sender.
     * @param data Data bundle containing message data as key/value pairs.
     *             For Set of keys use data.keySet().
     */
    // [START receive_message]
    @Override
    public void onMessageReceived(String from, Bundle data) {
        String message ;
        String title;
//        ID = Utils.getIDForPush("pushId",this);
//        if(ID == 0){
//            ID = 1;
//        }else {
//            ID += 1;
//        }
//        Utils.saveIDForPush("pushId",ID,this);
        Bundle bundle = data.getBundle("notification");
        if(bundle!= null){
        message = bundle.getString("body");
        title = bundle.getString("title");
            Log.d(TAG, "From: " + from);
            Log.d(TAG, "Message: " + message);}
        else {
            message ="";
            title = "NCMS";
        }

        mDbManager = LocalDataBaseManager.getInstance(this);
        if (from.startsWith("/topics/")) {
            Calendar c = Calendar.getInstance();
            SimpleDateFormat s = new SimpleDateFormat("ddMMyyyyhhmmss");
            String format = s.format(new Date());
            ID = Long.parseLong(format);
            String date = new SimpleDateFormat("dd-MM-yyyy HH:mm", Locale.ENGLISH).format(new Date());
            Warnings warnings = new Warnings();
            warnings.setWARNING_ID(ID);
            warnings.setWARNING_EN(message);
            warnings.setWARNING_AR(message);
            warnings.setSTART_DATE_TIME(date);
            warnings.setNotification_type(String.valueOf(Constant.NotificationType.PUSH));
            warnings.setSEVERITY("");
            warnings.setEND_DATE_TIME("");
            warnings.setUPDATE_NO("");
            mDbManager.insertNotificationInfo(warnings);
            // message received from some topic.
        } else {
            // normal downstream message.
        }

        // [START_EXCLUDE]
        /**
         * Production applications would usually process the message here.
         * Eg: - Syncing with server.
         *     - Store message in local database.
         *     - Update UI.
         */

        /**
         * In some cases it may be useful to show a notification indicating to the user
         * that a message was received.
         */
//        KeyguardManager km = (KeyguardManager) this.getSystemService(Context.KEYGUARD_SERVICE);
//        boolean locked = km.inKeyguardRestrictedInputMode();
//
//        String release = android.os.Build.VERSION.RELEASE;
//
//
//        if (Integer.parseInt(String.valueOf(release.charAt(0))) < 5 && locked) {
//
//            this.stopService(new Intent(this, NotificationService.class));
//            Intent serviceIntent = new Intent(this, NotificationService.class);
//            this.startService(serviceIntent);
//
//        }
        sendNotification(title,message);
        // [END_EXCLUDE]
    }
    // [END receive_message]

    /**
     * Create and show a simple notification containing the received GCM message.
     *
     * @param message GCM message received.
     */
    private void sendNotification(String title,String message) {
        Intent intent = new Intent(this, MainActivity.class);
        intent.putExtra("message",message);
        intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0 /* Request code */, intent,
                PendingIntent.FLAG_ONE_SHOT);

        Uri defaultSoundUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
        NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this)
                .setSmallIcon(R.drawable.ncms_launcher)
                .setContentTitle(title)
                .setContentText(message)
                .setAutoCancel(true)
                .setSound(defaultSoundUri)
                .setContentIntent(pendingIntent);

        NotificationManager notificationManager =
                (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

        notificationManager.notify(0 /* ID of notification */, notificationBuilder.build());
    }
}

La información manifiesta para este servicio está siguiendo

 <service
        android:name=".gcm.MyGcmListenerService"
        android:exported="false" >
        <intent-filter>
            <action android:name="com.google.android.c2dm.intent.RECEIVE" />
        </intent-filter>
    </service>

Lo que me estoy perdiendo aquí.

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