When you're setting up the request, delete your proxy setup ie
request.Proxy = new WebProxy();
add the line in bold as indicated
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(AccountStatusLookUpURL);
request.Headers.Add("SOAPAction", "https://soa.nbf.ae/ICCSAccountLookup/ICCSAccountLookup");
request.ContentType = "text/xml; charset=\"utf-8\"";
request.Accept = "gzip,deflate";
request.Method = "POST";
request.ProtocolVersion = HttpVersion.Version10;
request.ClientCertificates.Add(new X509Certificate2(Common.CORE_PFXPath, Common.CORE_PFXPassword));
request.Proxy = GlobalProxySelection.GetEmptyWebProxy();
If you dont use a proxy or don't set the proxy type the request will try to auto-detect and then configure a proxy ...