public async Task <IActionResult> Edit(Receiver newValues)
        {
            //get session id (we will use it when updating data and handling errors)
            String sessionID_s = HttpContext.Session.GetString("Session");
            Guid   sessionID   = Guid.Parse(sessionID_s);
            Data   current     = new Data();

            Program.data.TryGetValue(sessionID, out current);
            current.Receiver = newValues;
            try
            {
                await _session.EditReceiver(newValues.ID, newValues.name, newValues.listening_time, newValues.rest_time, newValues.recovery_time);
            }
            catch (Exception e)
            {
                // log exception here
                current.message = e.Message.ToString() + " Error";
                await _session.Rollback();

                return(RedirectToAction("BeforeEdit", "Receiver"));
            }
            finally
            {
                _session.CloseTransaction();
            }
            current.edited = true;
            return(RedirectToAction("BeforeEdit", "Receiver"));
        }