I think we are being hit by a virus

Hello,

I think we are being hit by a virus. We use Jotform on our website to receive donations, and every 5 minutes someone or something is making $5 payments on the form. What would you recommend doing? Is this a breech on jotform's side? Or should I contact PayPal, or is it a matter of security on our Wordpress website itself? I look forward to hearing back from you

Hello,

First of all i think you should try to get in touch with the submitter(Jerry Smith alexsanchezinfocc@gmail.com). He may wants to cancel the transactions from PayPal. 

The only way i can think of is that after you submit the form, if you refresh the page, browser will asks to continue or cancel to re-submitting the form. And if you click continue then the form would've been re-submitted.

You can add a captcha field to your form as an additional confirmation.

Here is How to Add a Captcha Field.

Or you may want to try the widgets.