Captcha not loading during comment reply

Hello,

Thank you for the plugin, I just started using it.

It works fine in most cases, but when I click “reply” under a comment a new form shows up next to the comment in question but CF captcha doesn’t load. Instead just a placeholder is shown (see the image).

Any idea what causes this? Is this a known issue?

Thanks

The page I need help with: [log in to see the link]