We are getting duplicates for a single submission

One of our users filled in this form, http://form.jotform.us/form/42788214225153  two times and it was sent to the recipients at least 10 times for each submission.

Thanks

Did you embed this form on your website? Can you share us the link? It's possible that a conflict is causing the problem. Where there's a conflict, the button will usually appear as not working making users click the submit button multiple times. 

If it's a conflict, you can fix it by simply re-embedding the form using our iframe method: https://www.jotform.com/help/148-Getting-the-Form-iFrame-Code.

I would also suggest adding a captcha field in the form: https://www.jotform.com/help/205-How-to-Add-a-Captcha. The captcha will also help you prevent duplicate submissions.