RadGrid is not populated

hi, please help me what i am doing wrong in the followig code. RadGrid is empty, but the DataTable is getting data from DB:

<telerik:RadScriptManager ID="RadScriptManager1" runat="server"> 
    </telerik:RadScriptManager> 
    <!-- content start -->
    <telerik:RadAjaxManager ID="RadAjaxManager1" runat="server"> 
        <AjaxSettings> 
            <telerik:AjaxSetting AjaxControlID="RadGrid1"> 
                <UpdatedControls> 
                    <telerik:AjaxUpdatedControl ControlID="RadGrid1" LoadingPanelID="RadAjaxLoadingPanel1" /> 
                    <telerik:AjaxUpdatedControl ControlID="LBL_Surname" LoadingPanelID="RadAjaxLoadingPanel1" /> 
                    <telerik:AjaxUpdatedControl ControlID="TB_Surname" LoadingPanelID="RadAjaxLoadingPanel1" /> 
                    <telerik:AjaxUpdatedControl ControlID="LBL_Name" LoadingPanelID="RadAjaxLoadingPanel1" /> 
                    <telerik:AjaxUpdatedControl ControlID="TB_Name" LoadingPanelID="RadAjaxLoadingPanel1" /> 
                    <telerik:AjaxUpdatedControl ControlID="Btn_Search" LoadingPanelID="RadAjaxLoadingPanel1" /> 
                </UpdatedControls> 
            </telerik:AjaxSetting> 
        </AjaxSettings> 
    </telerik:RadAjaxManager> 
    <telerik:RadAjaxLoadingPanel ID="RadAjaxLoadingPanel1" runat="server"> 
    </telerik:RadAjaxLoadingPanel> 
    <!-- content end -->
    <telerik:RadSplitter ID="RadSplitter1" runat="server" Width="80%"> 
        <telerik:RadPane ID="RadPane1" runat="server" Width="99%"> 
            <telerik:RadGrid ID="RG_SearchResult" runat="server" Skin="Telerik" OnItemDataBound="RG_SearchResult_ItemDataBound"
                OnNeedDataSource="RG_SearchResult_NeedDataSource" OnDetailTableDataBind="RG_SearchResult_DetailTableDataBind"
                OnItemCommand="RG_SearchResult_ItemCommand" DataSourcePersistenceMode="NoPersistence"
                HeaderStyle-Font-Bold="true" Width="99%" PageSize="1000" PagerStyle-AlwaysVisible="true"
                ShowStatusBar="True" GridLines="None" AutoGenerateColumns="False"> 
                <MasterTableView Name="Level1" DataKeyNames="ID"> 
                    <Columns> 
                        <telerik:GridBoundColumn DataField="ID" HeaderText="ID" UniqueName="ID" Visible="false" /> 
                        <telerik:GridBoundColumn DataField="SurName" HeaderText="???????" UniqueName="SurName" /> 
                        <telerik:GridBoundColumn DataField="FirstName" HeaderText="???" UniqueName="FirstName" /> 
                        <telerik:GridBoundColumn DataField="PName" HeaderText="????????" UniqueName="PName" /> 
                    </Columns> 
                    <DetailTables> 
                        <telerik:GridTableView Name="Level2" DataKeyNames="ID" HierarchyLoadMode="ServerOnDemand"
                            Width="100%" BackColor="#EFEFFB"> 
                            <Columns> 
                                <telerik:GridButtonColumn CommandName="RollInfo" Text="???????" UniqueName="RollInfo" /> 
                                <telerik:GridButtonColumn CommandName="History" Text="???????" UniqueName="History" /> 
                                <telerik:GridButtonColumn CommandName="TechSpec" Text="???. ?????????" UniqueName="TechSpec" /> 
                                <telerik:GridBoundColumn DataField="ID" HeaderText="ID" UniqueName="ID" Visible="false" /> 
                                <telerik:GridBoundColumn DataField="PropCode" HeaderText="???" UniqueName="PropCode" /> 
                                <telerik:GridBoundColumn DataField="PropAddr" HeaderText="?????" UniqueName="PropAddr" /> 
                                <telerik:GridBoundColumn DataField="Owner" HeaderText="???" UniqueName="Owner" /> 
                            </Columns> 
                            <PagerStyle AlwaysVisible="True"></PagerStyle> 
                        </telerik:GridTableView></DetailTables> 
                    <ExpandCollapseColumn Visible="True"> 
                    </ExpandCollapseColumn> 
                    <PagerStyle AlwaysVisible="True"></PagerStyle> 
                </MasterTableView><HeaderStyle Font-Bold="True"></HeaderStyle> 
                <PagerStyle AlwaysVisible="True"></PagerStyle> 
            </telerik:RadGrid></telerik:RadPane> 
    </telerik:RadSplitter>

Select allOpen in new window

protected void Btn_Search_Click(object sender, EventArgs e) 
       { 
           DataTable dt = new DataTable(); 
           if (RBL_UType.SelectedValue == "0") 
               dt = KLIS.Helpers.myConnections.GetDataTableX("udsp_SearchByName", "Sirname", TB_Surname.Text, "Firstname", TB_Name.Text); 
           else if (RBL_UType.SelectedValue == "1") 
               dt = KLIS.Helpers.myConnections.GetDataTableX("udsp_SearchByFirm", "FirmName", TB_Name.Text); 
 
           RG_SearchResult.DataSource = dt; 
           RG_SearchResult.DataBind(); 
       }

Select allOpen in new window