JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
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 opened one of your form and did a test submission. It was successful because when I hit the submit button, it redirected me to the Thank You page.
Is this form embedded on a webpage? Please try to re-embed the form using the Iframe method in order to prevent script conflicts between the form and the webpage. Here's a guide: https://www.jotform.com/help/148-Getting-the-form-iFrame-code.
Let us know if you need further help. Thank you.