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 took a look at your account and all forms within it and non seems to be over quota. I presume that you had a form limit set on one of the forms, but have removed it after posting your question.
I do however see that you have posted another question here: https://www.jotform.com/answers/808416 with more details.
I have inspected the links on the other thread, and all of the forms there seem to be working properly as well.
Now I see that you have upgraded, but based on your current usage you are OK for the free plan as well. If you happen to get the same error message again, please do let us know.