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.
Please kindly check your form's Incomplete Payment: http://www.jotform.com/help/135-How-to-View-Incomplete-Payments. Check if the payment submission has landed there.
In addition, we advise to enable IPN (Instant Payment Notification) to your Paypal Account. Here's a guide on how you can do that: http://www.jotform.com/help/276-How-to-Enable-IPN-for-Paypal.
For you to understand why this is needed, please check this guide: http://www.jotform.com/help/272-Paypal-Incomplete-Payments-FAQ.
Hope that helps!