auto complete control is not working..this is my code

hi! dear frnds i want to make auto complete text box and my code is not working plz tell what is the problem in this code

<asp:TextBox ID="txtAreaName" runat="server" CssClass="txtArea"  placeholder="Enter Area to Search Dealers" Height="34px" Width="259px"></asp:TextBox>
                       <asp:AutoCompleteExtender ID="AutoCompleteExtender1" ServiceMethod="GetArea" MinimumPrefixLength="2"

                            runat="server" CompletionInterval="100" EnableCaching="true" CompletionSetCount="10" TargetControlID="txtAreaName" FirstRowSelected="true"></asp:AutoCompleteExtender>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data.OracleClient;
using System.Data;
using System.Configuration;
using System.Web.Services;
using System.Web.Services.Protocols;


namespace OnlinePropertyDealer.MasterPage
{
    public partial class OnlineDealers : System.Web.UI.MasterPage
    {
        protected void Page_Load(object sender, EventArgs e)
        {
        }

[System.Web.Services.WebMethod]
        [System.Web.Script.Services.ScriptMethod]
        public string[] GetArea(string prefixText, int count)
        //[System.Web.Script.Services.ScriptMethod()]
        //[System.Web.Services.WebMethod]
        //public static List<string> GetArea(string prefixText)
        {
            List<string> AreaNames = new List<string>();

            using (OracleConnection con = new OracleConnection())
            {
                con.ConnectionString = ConfigurationManager
                        .ConnectionStrings["conStr"].ConnectionString;
                using (OracleCommand cmd = new OracleCommand())
                {
                    cmd.CommandText = "select area_namr from area_table where " +
                    "area_name like @SearchText + '%'";
                    cmd.Parameters.AddWithValue("@SearchText", prefixText);
                    cmd.Connection = con;
                    con.Open();
                    using (OracleDataReader sdr = cmd.ExecuteReader())
                    {
                        while (sdr.Read())
                        {
                            AreaNames.Add(sdr["area_name"].ToString());
                        }
                    }
                    con.Close();
                    return AreaNames.ToArray();
                }
            }