public IActionResult OnPost(int id)
        {
            var temp = appointmentData.GetAppointmentById(id);

            if (temp == null)
            {
                return(RedirectToPage("~/NotFound"));
            }
            var temp2 = appointmentData.Delete(temp.Id);

            appointmentData.Commit();
            TempData["TempMessage"] = "The appointment is deleted!";
            return(RedirectToPage("./List"));
        }