Getting multiple submissions in my forms

So why would this happen?  We are a marketing company and we have several Jot Forms for several clients and they are all starting to get multiple submissions from the same person.

If you want to get only unique submissions on your form and prevent the same person submitting the form, you can use the Unique Submission feature of the form.

User guide : https://www.jotform.com/help/64-How-to-Set-Unique-Submissions-on-a-Form

I checked also your form and I see it was already using Captcha field. The Captcha will prevent already any spam only submission on the form.

I hope this help. Let us know if you need further assistance.

So this is the only way to prevent this?

Do you have any idea on why this happens?  Does the user's web browser submit again automatically?  I just don't have any understanding of why or how the same submission could get submitted again with out the user doing so.

One of our website owners has followed up with one of his users who swears they only filled the form out one time. 

If we turn on unique submissions, what happens when that same IP Address and browser needs to use the form again?  Our website owners won't get those?  Will Jotform not allow it?

Some browsers cache form data and if a user presses the back button on their browser to return to the form or another page, they may return to the submit page again.  This tends to happen most often on IOS devices from what I have seen.  Unfortunately, there is no way for us to prevent this browser behavior on our end.

If you enable unique submissions, it will prevent submission of the form if it is not a unique submission.