//Get Oprations as json array for Js Tabulator Library
 public IActionResult GetJsonOpr()
 {
     if (TempData["TutorModel"] != null)
     {
         UserCache    userCache    = JsonConvert.DeserializeObject <UserCache>(TempData["TutorModel"].ToString());
         PaymentModel paymentModel = new PaymentModel
         {
             User = userCache.Extract()
         };
         paymentModel.Operations = PaymentDB.GetOprList(userCache.UserId, GetConfiguration().GetConnectionString(DEFAULT_CONNECTION));
         TempData.Keep("TutorModel");
         return(Json(paymentModel.Operations));
     }
     return(null);
 }