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 think the one you're referring is the "Form Warning" message. Please follow the Steps below for your info.
1. Click “Preferences”.
2. Click “Advance Settings”.
3. Click “Edit Form Warning”.
4. Click and change “This field is required.” to “Whoops! looks like you missed something!”
5. Example: http://form.jotform.me/form/50443315634449
These steps provided by rsalvo will allow you to change your form warning messages.
Please feel free to contact us if you need further assistance.