Windows phone 7 get follower issue



When I trying to get a POST request with authentication (like update staus) my app works fine.
The problem show me when I trying to get a GET request with authentication (like Get followers).

This is a part of my code:

            url = sGetFollowerList(App.UserName, this.next_page);

            OAuthHeader = TwitterEngine.GetOAuthHeader(parameters, "GET", url, AuthConstants.ConsumerSecret, App.Token);

            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
            request.Method = "GET";
            request.Headers["Authorization"] = OAuthHeader;

            request.BeginGetResponse(new AsyncCallback(GetFollowerList_GetResponse), new object[] { request, null });

Anyone can help me?