Report Execution time

Hello am am trying to get a report data but the time for the report to execute on wiloan itself is like 1 minute when i try to get the data on my website via this code

  string ret = string.Empty;

            StreamWriter requestWriter;

            var webRequest = System.Net.WebRequest.Create(url) as HttpWebRequest;
            if (webRequest != null)
            {
                webRequest.Method = "POST";
                webRequest.ServicePoint.Expect100Continue = false;
                webRequest.Timeout = Timeout.Infinite;
                webRequest.KeepAlive = true;

                webRequest.ContentType = "application/json";
                //POST the data.
                using (requestWriter = new StreamWriter(webRequest.GetRequestStream()))
                {
                    requestWriter.Write("");
                }
            }

            HttpWebResponse resp = (HttpWebResponse)webRequest.GetResponse();
            Stream resStream = resp.GetResponseStream();
            StreamReader reader = new StreamReader(resStream);
            ret = reader.ReadToEnd();

i get 404 server returned not found this code works when the data is not that big when i make the from and To shorter
please advice thanks