JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
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.
You can set unique submissions on your form. Please follow the steps below:
#1- Click Preferences.
#2- Click Advanced in Preferences page.
#4- Finally, save your changes.
In addition, please have a look at this guide if you need more details about the issue: How-to-Set-Unique-Submissions-on-a-Form
If you need any further assistance, please don't hesitate to contact us.
Thank you for your asking.