DevExpress gridview grouping?

I use DevExpress v10.2.3 grouping GridView with asp.net MVC 4. I can get data from database and show them.

But I can't change any constraint. For example: sort by column. When I clicked to sort I get following pop up page.This page is opened When I every click to fire script. Any idea about this? May be this is an easy error, but I cant see it.

partialView

@Html.DevExpress().GridView(
settings =>
{
    settings.Name = "gvGrouping";
    settings.CallbackRouteValues = new { Controller = "Customer", Action = "PartialCustomers" };
    settings.Width = System.Web.UI.WebControls.Unit.Percentage(100);

    settings.Columns.Add("sno");
    settings.Columns.Add("Name");
    settings.Columns.Add("City");
    settings.Columns.Add("Ilce");
    settings.Columns.Add("Sokak").GroupIndex = 0;

    settings.Settings.ShowGroupPanel = true;

    settings.CustomCallback = (sender, e) =>
    {
        int layoutIndex = Int32.Parse(e.Parameters);
        DevExpress.Web.Mvc.MVCxGridView grid = (DevExpress.Web.Mvc.MVCxGridView)sender;

        grid.BeginUpdate();
        try
        {
            grid.ClearSort();
            switch (layoutIndex)
            {
                case 0:
                    grid.GroupBy(grid.Columns["Sokak"]);
                    break;
                case 1:
                    grid.GroupBy(grid.Columns["Sokak"]);
                    grid.GroupBy(grid.Columns["City"]);
                    break;
                case 2:
                    grid.GroupBy(grid.Columns["Name"]);
                    break;
            }
        }
        finally
        {
            grid.EndUpdate();
        }
        grid.ExpandAll();
    };
}).Bind(Model).GetHtml()

View

@model IEnumerable<mvc4devex.Models.Customers>
@{
    ViewBag.Title = "Customers";
}


<label for="GroupBy">GroupBy:</label>
<select id="GroupBy" onchange="gvGrouping.PerformCallback(this.value);">
    <option value="0">Sokak</option>
    <option value="1">Sokak, City</option>
    <option value="2">Name</option>
</select>
&nbsp;
<input type="button" value="Collapse All Rows" onclick="gvGrouping.CollapseAll();" />
&nbsp;
<input type="button" value="Expand All Rows" onclick="gvGrouping.ExpandAll();" />
<br /><br />
@Html.Partial("_PartialCustomers", Model)

This issue is caused for either of the following reasons:

• The GridView Extension defined in a separate PartialView contains additional tags;

• The Action specified within the CallbackRouteValues.Action property is implemented incorrectly (should return the PartialView with the GridView).