I want to solve hCaptcha-invisible via 2Captcha with VB.NET (selenium)

Question

I want to solve hCaptcha-invisible.

→https://2captcha.com/demo/hcaptcha-invisible

I successfully solved other hCaptcha. For example hCaptcha-difficult.
→https://2captcha.com/demo/hcaptcha?difficulty=difficult

But I can't solve hCaptcha-invisible.

My program code is almost same. The differences as only parameter of 'pageurl' and 'sitekey'.

Problem

In case hCaptcha-difficult, When I submit, it showed 'Success!' But in case hCaptcha-invisible, When I submit, hCaptcha image was displayed.

I tried to solve with the code below.

When I try solve invisible, I submit then hCaptcha image was displayed. Could you help me know my mistakes?

Thank you for your help.

        '■Fail.
        Dim targetURL = "https://2captcha.com/demo/hcaptcha-invisible"
        Dim sitekey = "f7de0da3-3303-44e8-ab48-fa32ff8ccc7b"

        '■Success!
        'Dim targetURL = "https://2captcha.com/demo/hcaptcha?difficulty=easy"
        'Dim sitekey = "41b778e7-8f20-45cc-a804-1f1ebb45c579"

        '■Success!
        'Dim targetURL = "https://2captcha.com/demo/hcaptcha?difficulty=difficult"
        'Dim sitekey = "f33236d2-3dff-4f1f-9aed-1dc3128a5f90"

'...omission...

        '------------------------------------------------------------
        'Get solve answer
        '------------------------------------------------------------
        Dim answer = stRetResponse.request
        Debug.Print("Token：" & answer)

        '------------------------------------------------------------
        'Input the answer into the textarea
        '------------------------------------------------------------
        Dim textarea1 = driver.FindElements(By.Name("h-captcha-response"))(0)
        driver.ExecuteScript($"arguments[0].value = '{answer}';", textarea1)
        ''Visualize textarea.
        'CType(driver, IJavaScriptExecutor).ExecuteScript("document.getElementsByName('h-captcha-response')[0].setAttribute('style', 'display: true; height: 20px;');")

        '------------------------------------------------------------
        'Input the answer into the 'data-hcaptcha-response' attribute
        '------------------------------------------------------------
        Dim iframe As IWebElement = driver.FindElement(By.CssSelector("#root > div > main > div > section > form > div > div > div > iframe"))
        driver.ExecuteScript($"arguments[0].setAttribute('data-hcaptcha-response', '{answer}');", iframe)

        '------------------------------------------------------------
        'Submit.
        '------------------------------------------------------------
        Dim form = driver.FindElements(By.CssSelector("#root > div > main > div > section > form"))(0)
        form.Submit()

enter image description here