public IHttpActionResult GetUser(decimal?id)
        {
            if (id == null)
            {
                throw new ArgumentNullException(nameof(id));
            }

            var loginModel = db.PR_GetUser(id).FirstOrDefault();

            if (loginModel == null)
            {
                return(NotFound());
            }

            if (loginModel.AccountNumber == null)
            {
                loginModel.AccountNumber = 0;
            }

            return(Ok(loginModel));
        }