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.
Yes, it is a normal function that after submission, it will go to the Thank You page. I cloned your form and I've found out that the Thank You page is being redirected to an external link. Here's a screenshot:
You can change the Thank You page through the Thank You wizard. Please refer to this guide: Setting-Up-the-Thank-You-Page
Hope that helps. Thank you.