What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
I have tested your form in Google Chrome and Captcha is working properly. However I have recreated your problem in Mozilla Firefox. After inspecting your website I noticed that you are using script block (source code) for embedding your form on website. We recommend using of iFrame code. You can try to replace source code with iFrame to see if the Captcha will load. In this article you can find out how to do it.
Hope this will help. Let us know if you need further assistance.