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.
The image you have attached seems to be broken.
However, I did send a test submission and I was able to submit your form successfully. I did not see an error message when I submitted the form.
Are you still encountering the issue? Did you embed the form on a website? If you did, please give us the URL of the website so we can further investigate it.
You can also send a screenshot of the error by following this guide: How to add screenshots/images to questions to the support forum?
I will wait for your response.