Value of label does not display at run time

<asp:UpdatePanel ID="updLbl" runat="server" UpdateMode="Conditional">
            <ContentTemplate>
                You are in
                <asp:Label ID="lblPos" runat="server"></asp:Label><sup>th</sup> Position
            </ContentTemplate>
        </asp:UpdatePanel>

public partial class _Default : System.Web.UI.Page 
{
    int pos;
    public delegate int  dlgtcaller(out int pos);
    protected void Page_Load(object sender, EventArgs e)
    {
        Async objCls = new Async();
        dlgtcaller call = new dlgtcaller(objCls.AsyncMethod);
        IAsyncResult result = call.BeginInvoke(out pos, new AsyncCallback(cbMethod), null);
    }
    public void cbMethod(System.IAsyncResult ar)
    {
        AsyncResult result = (AsyncResult)ar;
        dlgtcaller caller = (dlgtcaller)result.AsyncDelegate;
        int returnValue = caller.EndInvoke(out pos, result);
        lblPos.Text = pos.ToString();
    }
}

public class Async
{
     public int AsyncMethod(out int pos)
    {
        string SQL = "SELECT count(id) FROM test";
        string ConnectionString = "server=DEV-PC4\\SQLEXPRESS;Initial Catalog=Pradeep;User ID=******;Password=******;";
        SqlConnection con = new SqlConnection(ConnectionString);
        SqlCommand cmd = new SqlCommand(SQL, con);
        con.Open();
        pos = Convert.ToInt32(cmd.ExecuteScalar());
        return pos;
    }
}