Non-Paypal user confirming receipt of item

Description

Hello all,
I sent a digital good to a customer, who in turn paid for it. The funds are currently pending/on hold in my account. I sent them an invoice for the item, and the buyer did not log into PayPal to complete the transaction, and instead checked out and paid for the item as a guest. The buyer told me that he received the item, however, the funds are still on hold on my account. When I open the transaction in the My Summary section, I get this error message: « You have successfully updated shipment information. You’ll get your money within 1 day of delivery. »
Neither I nor the buyer are sure of where to confirm delivery on PayPal (as he does not even have an account and checked out without creating one). Any way to resolve this?
Thanks!