jQuery AJAX not calling Web Method in ASP.Net

in default.aspx i am calling web method. bt every time its going to error method.

code is...

function login(btn) {
            alert('a');
            var email = document.getElementById("txtUserName").value;
            var password = document.getElementById("txtPass").value;
            if (email == "" || password == "") {
                alert('Fill up data');
                return;
            }
            else {
                /* send the link to fetch details */
                var check = CheckRadio(btn);
                var input = email + " " + password + " " + check;/* detect by space */
                alert(input);
                $.ajax(
                {
                    type: 'POST',
                    url: '/Default.aspx/Login',
                    data: '{\'inputText\':\'' + input + '\'}',
                    dataType: 'json',
                    contentType: 'application/json; charset=utf-8',
                    success: function (response) {
                        if (response != null && response.d != null) {
                            alert('done');
                        }
                    },
                    failure: function (response) {
                        alert('Sorry! Operation failed.');
                    },
                    error: function (response) {
                        alert('Sorry! Error.');
                    },
                });
            }

function CheckRadio(rd) {
            var tr = rd.parentNode.parentNode;
            var radiobutton = tr.getElementsByTagName('input');
            for (var i = 0; i < radiobutton.length; i++) {
                if (radiobutton[i].checked) {
                    return (radiobutton[i].nextSibling.textContent);
                }
            }
        }

webmethod :

[WebMethod(EnableSession = true)]
        public string Login(string inputText)
        {

            int i = 0;
            string[] ip = inputText.Split(' ');

            User_DAL obj = new User_DAL();
            DataTable dt = obj.Login(ip[0].ToString(), ip[1].ToString(), ip[2].ToString());
            if (dt.Rows.Count >= 1)
                return string.Format("{0}", "Success");
            else
            return string.Format("{0}", "Wrong email & password !");
        }

thank u..