public IActionResult CreateCustomer([FromBody] CustomerViewModel customerVm)
 {
     if (!ModelState.IsValid)
     {
         IEnumerable <ModelError> allErrors = ModelState.Values.SelectMany(v => v.Errors);
         return(new BadRequestObjectResult(allErrors));
     }
     _customerService.Add(customerVm);
     _customerService.SaveChanges();
     return(new OkObjectResult(customerVm));
 }