Admin Login Home Controller

public ActionResult admlogin(Admin a)
        {

            Admin res = db.Admins.Where(x => x.admin_email == a.admin_email & x.admin_password == a.admin_password).FirstOrDefault();
            if (res != null)
            {
                Session["adm"] = res;
                return RedirectToAction("index", "Admin");
            }

            else if (res == null)
            {

                ViewBag.message = "The Email you have entered is not registered yet. Please Register Your Account Here";
                return View();
            }
            else
            {
                ViewBag.message = "Email or Password is incorrect";
                return View();
            }
        }