Why does the FrameLoadEnd event fire only once?

Question

C++ / C#

Like I click on the button, I load the page, everything works and the method works.

private void button1_Click(object sender, EventArgs e)
        {
            browser.Load($"{url}{WebUtility.UrlEncode(textBox1.Text)}"); // Пример ссылки - https://kad.arbitr.ru/Card/4f2e853a-d214-4a0b-aa65-f2bfd5fc4dcc
        }

Then on the second button this code.

The page loads, but for some reason the method that the page is loaded does not work, although browser.Load () is there and there.

I'm not unsubscribing from the event anywhere. What's the catch?

string GoToPrintCardAddress = angle.QuerySelector("#b-case-header > ul.b-case-overview.g-ec > li.case-print > a").GetAttribute("href");
                browser.Load(GoToPrintCardAddress); // Срабатывает и переносит на другую страницу

// пример ссылки - https://kad.arbitr.ru/PrintCard/4f2e853a-d214-4a0b-aa65-f2bfd5fc4dcc