Thanks for reaching out to us, Codybiroth.
I understand that you need to get your money back. I'm here to help you.
You'll want to verify how your contractor processed the refund. There are two ways on how to pay a contractor, either Online bill pay or direct deposit. We can cancel the payment and process a refund if you used any of these services. Since you mentioned that you paid them by cash, so there's no way to accept refunds within QuickBooks Online.
Also, I noticed that you tagged this post as QuickBooks Payments (Merchant Services). This service is used to accept payments from your customers. This is not ideal to receive refunds from your contractors or vendors.
Here's the article for your reference on how to record a refund in QuickBooks Online: Enter a refund from a vendor.
I'll be here if you need more help. Take care!