FaceBook Login Error: The domain of this URL isn't included in the app's domains

hello sir,

actually when i log in my side through facebook it throws error like

{
   "error": {
      "message": "Can't load URL: The domain of this URL isn't included in the app's domains. To be able to load this URL, add all domains and sub-domains of your app to the App Domains field in your app settings.",
      "type": "OAuthException",
      "code": 191,
      "fbtrace_id": "GtkcKNLrKQB"
   }
}

how can i solved it kindly help me. my code is

            FaceBookConnect.API_Key = Convert.ToString(ConfigurationManager.AppSettings["AppID"]);
            FaceBookConnect.API_Secret = Convert.ToString(ConfigurationManager.AppSettings["AppSecret"]);


            //Login Using Facebook
            if (!IsPostBack)
            {
                try
                {
                    if (Session["chksession"].ToString() == null)
                    {

                    }
                    else
                    if (Session["chksession"].ToString() == "Facebook")
                    {
                        ObjCtrl.validateLogin();
                        if (Request.QueryString["error"] == "access_denied")
                        {
                            ClientScript.RegisterStartupScript(this.GetType(), "alert", "alert('User has denied access.')", true);
                            return;
                        }

                        string code = Request.QueryString["code"];
                        if (!string.IsNullOrEmpty(code))
                        {
                            yb_user_details ObjUser = new yb_user_details();
                            yb_ctrlbind ObjCtrl = new yb_ctrlbind();
                            string[] returnval;
                            var utcdiff = TimeZone.CurrentTimeZone.GetUtcOffset(new DateTime());//get the difference from utc time
                            var utctime = utcdiff.TotalMinutes.ToString();

                            string data = FaceBookConnect.Fetch(code, "me?fields=id,name,email");
                            FaceBookUser faceBookUser = new JavaScriptSerializer().Deserialize<FaceBookUser>(data);
                            faceBookUser.PictureUrl = string.Format("https://graph.facebook.com/{0}/picture", faceBookUser.Id);
                            returnval = ObjUser.yb_ins_social_signup(faceBookUser.Name, "", faceBookUser.Email, "", 2, faceBookUser.Id, "Facebook", 0, DateTime.UtcNow.ToString()).Split(',');
                            if (returnval[0] != "5")
                            {
                                DateTime dt = Convert.ToDateTime(DateTime.UtcNow.ToString());
                                string setutime = dt.AddMinutes(Convert.ToDouble(utctime)).ToString();
                                HttpContext.Current.Session["YAAD_LAST_SEEN"] = setutime;
                                HttpContext.Current.Session["YAADUID"] = returnval[1].ToString();
                                addCookies(returnval[1].ToString(), faceBookUser.Email, faceBookUser.Name + ' ' + "");
                                Response.Redirect("UserTimeline/timeline.aspx");
                                //ObjCtrl.MailSend("mkmanaskumar@gmail.com",unamep,"Welcome to Yaadbook", Populatebody(firstname + ' ' + lastname, DateTime.UtcNow.ToShortDateString()));
                            }
                        }
                    }
                }
                catch
                { }
            }