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.
Actually, the form is save but you have to navigate to the last page to see it. With regards on deleting form from the My Forms section, I am able to replicate the same issue with not able to delete a form. But I don't see the error.
I would advise to replace your API key with a new one and see if that resolves the error. You can generate an API key to your Account - API section: https://www.jotform.com/myaccount/api
By the way, I have this thread forwarded to our developers. For now, you may consider using our own plugin for Wordpress:
Using this plugin, you have to create the form into our website. You have to click on the Jotform Icon form your post/page to add a form.
This app is made by a 3rd party developer, so it is not possible for us to fix the problems on it. Please post your request here instead: