Android Question Problem in INSERT query using okhttputils

    Dim HttpJob1 As HttpJob
    HttpJob1.Initialize("",Me)
        
    HttpJob1.PostString("https://abc.def.com/command1",JSON)
    HttpJob1.GetRequest.SetContentType("application/json")

    Wait For (HttpJob1) JobDone(HttpJob1 As HttpJob)
    If HttpJob1.Success Then
        Log(HttpJob1.GetString)
        ' = HttpJob1.GetString
    Else
        ' = HttpJob1.ErrorMessage
        ToastMessageShow(HttpJob1.ErrorMessage,True)
        Return
    End If
    HttpJob1.Release

 public class insertKOTController : Controller
    {
        public ActionResult Index()
        {
            return View();
        }
        public class KotDetail1
        {
            public string AddKot(KotDetail kd)
            {
                DateTime dt = DateTime.Now;
                string sqlFormattedDate = dt.Date.ToString("yyyy-MM-dd HH:mm:ss");
                string cs = ConfigurationManager.ConnectionStrings["Model8"].ConnectionString;
                using (SqlConnection con = new SqlConnection(cs))
                {
                    SqlCommand com = new SqlCommand("DKTinsertKotProc", con);
                    com.CommandType = CommandType.StoredProcedure;
                    com.Parameters.AddWithValue("@KoTNo", kd.KotNo);
                    com.Parameters.AddWithValue("@KotDate", dt);
                    com.Parameters.AddWithValue("@UnqNo", kd.unqno);
                    com.Parameters.AddWithValue("@ItemPcKey", kd.ItemPcKey);
                    com.Parameters.AddWithValue("@ItemCode", kd.ItemCode);
                    com.Parameters.AddWithValue("@Quantity", kd.Quantity);
                    com.Parameters.AddWithValue("@Rate", kd.Rate);
                    com.Parameters.AddWithValue("@TaxRate", kd.TaxRate);
                    com.Parameters.AddWithValue("@Amount", kd.Amount);
                    com.Parameters.AddWithValue("@Status", kd.Status);
                    com.Parameters.AddWithValue("@Reason", kd.Reason);
                    com.Parameters.AddWithValue("@PreferencePckey", kd.preferencePckey);
                    com.Parameters.AddWithValue("@ItemCategory", kd.itemcategory);
                    con.Open();
                    int i = com.ExecuteNonQuery();
                    con.Close();
                    if (i >= 1)
                    {
                        return "Record Added Successfully";

                    }
                    else
                    {
                        return "Record Not Added";

                    }
                }
            }
        }
        static KotDetail1 controller = new KotDetail1();
        public JsonResult AddKot(KotDetail kd)
        {
            var response = controller.AddKot(kd);
            return Json(response, JsonRequestBehavior.AllowGet);
        }
    }

 try
 {
 
 }
 catch (Exception e)
 {
   return e.ToString();
 }

public KotDetail TemplateKot()