Thanks for reaching out.
There is no popup found in the given URL, even after scrolling down. I would suggest you to avoid using any custom code, as we don’t provide any support or investigation to the custom coding or related issues.
If you still want to add the code, I recommend you to add it into the header or footer. Please find the details on how to add code in the header or footer in this article.
Please remember that we don’t offer any support to the Custom Codes and Third Party plugins.
Alternatively, you can use the bundled plugin ConvertPlus, to create popups you want.
Hope it helps.