Android Servis Arka Planda Çalışmıyor

Merhaba Arkadaşlar Android servis oluşturdum. Bu servis konum güncellenince  api çağırıyor ve veri kaydediyor. Uygulama ön planda olunca sorun yok ancak arka plana alınca servisim çalışmıyor . Sebebi ne  olabilir ? Servisim aşağıdaki gibidir.

public class VehicleGPSTrackerService extends Service {

    private LocationListener listener;
    private LocationManager locationManager;
    boolean gps_enabled = false;
    private Location llocation;
    private static final long MIN_TIME_BW_UPDATES = 1000 * 5 * 1; // 5 saniye

    public Coordinate lastCoordinate;

    TelephonyManager mTelephonyManager;

    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {

        Toast.makeText(this,getBaseContext().getResources().getString(R.string.tracking_on_started), Toast.LENGTH_SHORT).show();
        Log.e("onStartCommand", "GPS Service onStartCommand");

        lastCoordinate = new Coordinate();
        lastCoordinate.Latitude =0;
        lastCoordinate.Longitude = 0;

        try {
            locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);

            gps_enabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);


            if(!isNetworkAvailable(getBaseContext()))
            {
                Intent i = new Intent("location_update");
                i.putExtra("status", getBaseContext().getResources().getString(R.string.internet_connection_notfound));
                sendBroadcast(i);
            }

            if(!gps_enabled)
            {
                Intent i = new Intent("location_update");
                i.putExtra("status",  getBaseContext().getResources().getString(R.string.cannot_gps_data));
                sendBroadcast(i);
            }


            if (isNetworkAvailable(getBaseContext()) && gps_enabled)
            {
                if (locationManager != null) {
                    if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {

                        return Service.START_STICKY;
                    }
                    llocation = locationManager.getLastKnownLocation(locationManager.GPS_PROVIDER);
                    updateWithNewLocation(llocation);
                    //locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER,MIN_TIME_BW_UPDATES,0, this.listener);
                    locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,MIN_TIME_BW_UPDATES,0, this.listener);
                }
            }
        }
        catch (Exception e)
        {
            Log.e("gpsserviceexception",e.getMessage());
        }

        return super.onStartCommand(intent, flags, startId);


    }

    public boolean isNetworkAvailable(final Context context) {
        final ConnectivityManager connectivityManager = ((ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE));
        return connectivityManager.getActiveNetworkInfo() != null && connectivityManager.getActiveNetworkInfo().isConnected();
    }

    public void updateWithNewLocation(Location location)
    {
        listener = new LocationListener() {

            @Override
            public void onLocationChanged(Location location)
            {
                lastCoordinate = new Coordinate();
                double lat = location.getLatitude();
                double longi = location.getLongitude();
                lastCoordinate.Latitude =lat;
                lastCoordinate.Longitude = longi;

                DateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
                Date date = new Date(location.getTime());
                String formatted = format.format(date);

                final JSONObject headerObject = new JSONObject();
                final JSONObject params = new JSONObject();
                try
                {
                    JSONObject coordinate = new JSONObject();
                    coordinate.put("Latitude",lastCoordinate.Latitude);
                    coordinate.put("Longitude",lastCoordinate.Longitude);

                    JSONArray jsonArrayLogs = new JSONArray();

                    params.put("Status", EnumHelpers.EnumStatus.Active.getValue());
                    params.put("Coordinate", coordinate);
                    params.put("LastInfoDate",formatted);

                    jsonArrayLogs.put(params);

                    headerObject.put("UserId", AppEngine.CURRENT_USER.getId());
                    headerObject.put("ActiveDeviceId",getDeviceImei());
                    headerObject.put("Details",jsonArrayLogs);

                    Log.e("AktiveData",headerObject.toString());

                    SentDataToVolley(headerObject);
                }
                catch (Exception e){}

                Intent i = new Intent("location_update");
                i.putExtra("status", getBaseContext().getResources().getString(R.string.active));
                sendBroadcast(i);
            }

            @Override
            public void onStatusChanged(String provider, int status, Bundle extras) {

            }

            @Override
            public void onProviderEnabled(String provider) {

                Intent i = new Intent("location_update");
                i.putExtra("status", getBaseContext().getResources().getString(R.string.active));
                sendBroadcast(i);
            }

            @Override
            public void onProviderDisabled(String provider) {

                final JSONObject headerObject = new JSONObject();
                final JSONObject params = new JSONObject();
                try
                {
                    JSONObject coordinate = new JSONObject();
                    coordinate.put("Latitude",0);
                    coordinate.put("Longitude",0);

                    JSONArray jsonArrayLogs = new JSONArray();

                    params.put("Status", EnumHelpers.EnumStatus.NoGpsSignal.getValue());
                    params.put("Coordinate", coordinate);
                    params.put("LastInfoDate",getCurrentDate());

                    jsonArrayLogs.put(params);

                    headerObject.put("UserId", AppEngine.CURRENT_USER.getId());
                    headerObject.put("ActiveDeviceId",getDeviceImei());
                    headerObject.put("Details",jsonArrayLogs);

                    Log.e("NoSignalData",headerObject.toString());

                    SentDataToVolley(headerObject);
                }
                catch (Exception e){}

                Intent i = new Intent("location_update");
                i.putExtra("status", getBaseContext().getResources().getString(R.string.cannot_gps_data));
                sendBroadcast(i);
            }
        };
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        Toast.makeText(this, getBaseContext().getResources().getString(R.string.stop_tracking), Toast.LENGTH_LONG).show();

        final JSONObject headerObject = new JSONObject();
        final JSONObject params = new JSONObject();
        try
        {
            JSONObject coordinate = new JSONObject();
            coordinate.put("Latitude",lastCoordinate.Latitude);
            coordinate.put("Longitude",lastCoordinate.Longitude);

            JSONArray jsonArrayLogs = new JSONArray();

            params.put("Status", EnumHelpers.EnumStatus.StopTracking.getValue());
            params.put("Coordinate", coordinate);
            params.put("LastInfoDate",getCurrentDate());

            jsonArrayLogs.put(params);

            headerObject.put("UserId", AppEngine.CURRENT_USER.getId());
            headerObject.put("ActiveDeviceId",getDeviceImei());
            headerObject.put("Details",jsonArrayLogs);

            Log.e("StopTrackingData",headerObject.toString());

            SentDataToVolley(headerObject);
        }
        catch (Exception e){}


        if(locationManager != null){
            //noinspection MissingPermission
            locationManager.removeUpdates(listener);
        }
    }

    public void SentDataToVolley(final JSONObject headerObject )
    {

        RequestQueue getRequestQueue = Volley.newRequestQueue(getApplicationContext());

        JsonObjectRequest jsonObjReq = new JsonObjectRequest(Request.Method.POST, UrlConfig.VOLLEY_MOBILEGPSLOG, headerObject, new Response.Listener<JSONObject>() {
            @Override
            public void onResponse(JSONObject response)
            {
                Log.e("onResponse", response.toString());
            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error)
            {
                VolleyLog.d("onErrorResponse", "Error: " + error.getMessage());
                Log.e("Oonfail", error.toString());
            }
        }) {
            @Override
            public Map<String, String> getHeaders() throws AuthFailureError {
                HashMap<String, String> headers = new HashMap<String, String>();
                headers.put("Content-Type", "application/json; charset=utf-8");
                headers.put("Authorization-Token", ConstansApi.API_KEY);
                return headers;
            }
        };
        jsonObjReq.setRetryPolicy(new DefaultRetryPolicy(60000,    DefaultRetryPolicy.DEFAULT_MAX_RETRIES,    DefaultRetryPolicy.DEFAULT_BACKOFF_MULT));

        // Adding request to request queue
        getRequestQueue.add(jsonObjReq);

    }

    public String getCurrentDate()
    {
        Calendar c = Calendar.getInstance();
        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String strDate = format.format(c.getTime());

        return strDate;
    }

    private String getDeviceImei() {

        mTelephonyManager = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
        String deviceid = mTelephonyManager.getDeviceId();
        Log.d("msg", "DeviceImei " + deviceid);
        return deviceid;
    }

}

Bu servisi de şu şekilde çağırıyorum

 Intent i =new Intent(MainActivity.this,VehicleGPSTrackerService.class);
                startService(i);

manifast.xml dosyası da şu sekildedir

 <service
            android:name=".VehicleGPSTrackerService"
            android:enabled="true"
            android:exported="false"/>