Get value from an html Windows Form c#

Question

Hello I would like to take this value, it is a class inside the other, I am trying this code but it does not return the value.

private void button1_Click(object sender, EventArgs e)
    {
        string s = string.Empty;
        foreach (HtmlElement el in webBrowser1.Document.GetElementsByTagName("span"))

            if (el.GetAttribute("classname") == "point")
            {
                lb_show.Text = el.InnerText;
                //ou
                //lb_show.Text = el.InnerHTML;
            }