When I am posting data by POST and PUT method to web API using ASP.NET MVC controller getting error message status code: 405

{StatusCode: 405, ReasonPhrase: 'Method Not Allowed', Version: 1.1, Content: System.Net.Http.StreamContent, Headers: {   Pragma: no-cache   Cache-Control: no-cache   Date: Mon, 16 Sep 2019 03:31:46 GMT   Server: Microsoft-IIS/10.0   X-AspNet-Version: 4.0.30319   X-Powered-By: ASP.NET   Content-Length: 73   Allow: GET   Content-Type: application/json; charset=utf-8   Expires: -1 }}

 public ActionResult Insert(Student obj)
        {
            var client = new HttpClient();
            string stringData = JsonConvert.
        SerializeObject(obj);
            var contentData = new StringContent
        (stringData, System.Text.Encoding.UTF8,
        "application/json");
            HttpResponseMessage response = client.PostAsync
        ("http://localhost/api/student/", contentData).Result;
            ViewBag.Message = response.Content.
        ReadAsStringAsync().Result;
            return View(obj);

        }
#PUT METHOD
        public ActionResult Update(Student sdnt)
        {
            var client = new HttpClient();
            string stringData = JsonConvert.SerializeObject(sdnt);
            var contentData = new StringContent(stringData,
        System.Text.Encoding.UTF8, "application/json");
            HttpResponseMessage response = client.PutAsync
        ("http://localhost/api/student/" + sdnt.STDNT_ID,
        contentData).Result;
            ViewBag.Message = response.Content.
        ReadAsStringAsync().Result;
            return View("Insert");
        }