Invalid redirecturi: Given URL is not allowed by the Application configuration.

public partial class CS : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        FaceBookConnect.API_Key = "309542139130513";
        FaceBookConnect.API_Secret = "db5fc4d873c49d1d9ed5b3dcee3d338f";
        if (!IsPostBack)
        {
            string code = Request.QueryString["https://graph.facebook.com/oauth/authorize?"];
            if (!string.IsNullOrEmpty(code))
            {
                string data = FaceBookConnect.Fetch(code, "me/friends");
                FaceBookData facebookData = new JavaScriptSerializer().Deserialize<FaceBookData>(data);
                foreach (FaceBookUser user in facebookData.Data)
                {
                    user.PictureUrl = string.Format("https://graph.facebook.com/{0}/picture", user.Id);
                }
                gvFriends.DataSource = facebookData.Data;
                gvFriends.DataBind();
            }
        }
    }
    protected void btnFetch_Click(object sender, EventArgs e)
    {
        FaceBookConnect.Authorize("user_photos,friends_photos", Request.Url.AbsoluteUri);
    }

}

public class FaceBookData
{
    public List<FaceBookUser> Data { get; set; }
}

public class FaceBookUser
{
    public string Id { get; set; }
    public string Name { get; set; }
    public string PictureUrl { get; set; }
}

Then am getting following error.

"error": {
      "message": "Invalid redirect_uri: Given URL is not allowed by the Application configuration.",
      "type": "OAuthException",
      "code": 191

Show me solution as soon as possible.