Should the HttpPost Contact method look like this instead?

AppControllerSnippet.cs

        [HttpPost]
        public IActionResult Contact(ContactViewModel model)
        {
            var email = Startup.Configuration["AppSettings:SiteEmailAddress"];
            if (string.IsNullOrWhiteSpace(email))
            {
                ModelState.AddModelError("", "Unable to send message: invalid server configuration.");
            }

            if (ModelState.IsValid)
            {
                if (_mailService.SendMail(email, email, $"contact message from {model.Name}", model.Message))
                {
                    ModelState.Clear();
                    ViewBag.Message = "Message sent - thank you!!!";
                }
            }

            return View();
        }