public IHttpActionResult Post(SmtpModel model)
        {
            try
            {
                if (!ModelState.IsValid)
                {
                    return(BadRequest(ModelState));
                }

                _smtpService.InsertAsync(model);

                return(Ok());
            }
            catch (Exception ex)
            {
                return(InternalServerError(ex));
            }
        }