Ajax AutoCompleteExtender VB.NET

Hi, I use a autocompleteextender for a multiline textbox and it doesn't work but the debug won't show me any errors.
Thks for youtr help

aspx

<asp:ToolkitScriptManager ID="ScriptManager1" runat="server">
                                <Services>
                                    <asp:ServiceReference Path="MyService.asmx" />
                                </Services>
                            </asp:ToolkitScriptManager>
                            <asp:TextBox ID="txtDescAdd" runat="server" Width="537px" Height="111px" TextMode="MultiLine"></asp:TextBox>
                            <asp:AutoCompleteExtender runat="server" ID="autoComplete1" TargetControlID="txtDescAdd"
                                ServicePath="MyService.asmx" ServiceMethod="GetDescription" MinimumPrefixLength="1"
                                EnableCaching="true" />


asmx.vb

    Public Function GetDescription(ByVal prefixText As String, ByVal count As Integer) As String()
        Dim strSql As String = ("SELECT top " + count + " id_ts, description from timesheet where id_user = " + ADTools.GetUserID(My.User.Name).ToString + " and description like '" + prefixText + "%'")
        Dim conn = New SqlConnection(ConfigurationManager.ConnectionStrings("ConnectionTS").ConnectionString)
        Dim command = New SqlCommand(strSql, conn)
        Dim reader As SqlDataReader = command.ExecuteReader
        Dim temp As New List(Of String)
        While reader.Read
            temp.Add(CType(reader("description"), String))
        End While
        conn.Close()
        Return temp.ToArray()
    End Function
End Class

Select allOpen in new window