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 was able to replicate the issue when I tried downloading a single or multiple PDF file. The solution here is to reset the PDF template using the PDF Designer. Here's how:
In the Submissions page, click the "PDF" button and then select the "Customize PDF" option.
In the PDF Designer, please click the "Reset" button at the top right.
Click the "Save" button and try downloading the PDF form submissions again.
Hope that helps. Thank you.