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'm sorry for the trouble caused to you.
I did test your form and I am unable to replicate the issue you are having. I was able to submit your form successfully and thank you message was also displayed. Please check the screenshot below:
Have you embedded your form in any webpage? Please share the webpage URL and we will take a look.
I would suggest you to please try embedding your form using its iFrame embed code and see if that solves your problem. The following guide should help you how to grab your form's iFrame embed code: https://www.jotform.com/help/148-Getting-the-form-iFrame-code
We will wait for your response.