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.
The 502 error was caused due to an outage at Amazon. We use them as our main file storage provider and when they had an outage, it caused our servers to no longer be able to process submissions.
This has since been fixed on our end and Amazon's. There should no longer be any issues with submitting forms or uploading files.