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.
To check if your recipient address is in the bounce list, you can follow this guide: http://www.jotform.com/help/262-How-to-remove-your-email-address-from-bounce-list
To prevent this happening, I would strongly suggest checking this link: http://www.jotform.com/help/208-How-to-setup-email-alerts-to-prevent-email-bouncing-related-issues
You can also check if the emails were successfully sent or not by following this other guide: http://www.jotform.com/help/293-How-to-view-all-your-form-Email-History
Do let us know if that works.