Is it possible to issue a refund through the JotForm system?

We need to issue a refund to a donor. Is there a means of doing that though our JotForm account or is this solely a function of our payment gateway? We are using Square as our gateway.

Since JotForm does not process the payment you need to issue the refund from your payment gateway. 

Here's an article about refunds on Square that may help you: https://squareup.com/help/us/en/article/5060-process-refunds