Menu display problem

[Pritam]

hi,

I have a when displaying menu Item for 3 rd child label..

RootItems are generated from Page_Load..
Code Snippet Below............
==================================================
SqlDataAdapter sda = new SqlDataAdapter("SELECT CAM_CGID,CAM_CNAM FROM E_CAT_MST WHERE CAM_CLVL=1", conn);
        DataTable dt = new DataTable();
        sda.Fill(dt);
        RadMenu1.DataSource = dt;
        RadMenu1.DataTextField = "CAM_CNAM";
        RadMenu1.DataValueField = "CAM_CGID";
         RadMenu1.DataBind();

===================================================
===============At the 2nd label the item  is loaded from Webservice====================
<Script>
 function itemPopulating(sender, eventArgs) {
        var item = eventArgs.get_item();
        var context = eventArgs.get_context();
        context["CAM_CPID"] = item.get_value();
             
    }
</Script>
==================================
===============Telerik Menu=======================
<telerik:RadMenu ID="RadMenu1" runat="server" 
            OnClientItemPopulating="itemPopulating" Flow="Vertical" Height="500" EnableRootItemScroll="true"
            DefaultGroupSettings-Height="300" EnableRoundedCorners="true" 
            EnableShadows="true">
             <WebServiceSettings Path="WebService2.asmx" Method="WebServiceMethodName" UseHttpGet="false"  />
    <LoadingStatusTemplate>
        <asp:Image runat="server" ID="LoadingImage" ImageUrl="~/ajax-loader.gif" ToolTip="Loading..."
            Width="15px" Height="15px" ImageAlign="Left"/>
    </LoadingStatusTemplate> 
=======================================================================
==============================Webservice Code==============================
 public RadMenuItemData[] WebServiceMethodName(RadMenuItemData item, object context)
    {
        DataTable productCategories = GetProductCategories(item.Value);
        List<RadMenuItemData> result = new List<RadMenuItemData>();
        foreach (DataRow row in productCategories.Rows)
        {
            RadMenuItemData itemData = new RadMenuItemData();
            itemData.Text = row["CAM_CNAM"].ToString();
            itemData.Value = row["CAM_CGID"].ToString();
        
                itemData.ExpandMode = MenuItemExpandMode.WebService;
                  result.Add(itemData);
        }
        return result.ToArray();
    }

   public DataTable GetProductCategories(string value)
    {
        DataTable dt = new DataTable();
        SqlDataAdapter sda = new SqlDataAdapter("SELECT CAM_CNAM,CAM_CGID  FROM E_CAT_MST WHERE  CAM_CLVL <> 1               AND CAM_CPID=" + value, conn);
        return dt;
    }
=========================================================================

Above is the total code snippet..It is working fine for 2nd label..But in 3rd Label menu item is collapsed..

Pls help....