Buyer disputing payment on PayPal

This buyer agreed to purchase an account in installments, paying $600 upfront knowing he would have a payment schedule to repay the remaining $600. The buyer agreed to all the terms and conditions of my services, including a no refunds policy, even if they decide they no longer want to buy, my Recall Protection Policy etc. Upon realizing what they have agreed to, even though it was explicitly laid out and required his confirmation, which he did provide and agree to all terms, he claims to not have understood and wanted a refund. I explained to him everything in detail before, and clarified everything afterwards.

He is currently disputing the charge on PayPal. If he agrees to continue making his payments and cancels the dispute, this can be resolved. If PayPal denies his claim, he is a scammer and our deal is void.