A buyer has 3 days to respond to a delivery. The buyer can either ask for revision or accept the delivery. But if the buyer did not respond to the delivery within 72 hours, the order will be marked as completed automatically. And the fund will be released to the seller (actually added to the queue for 14 day clearing period [7 days for top-rated & "Seller Plus" members] ). After the order completion, the buyer can leave feedback/rating but he/she will not be able to ask for any revisions. If a buyer wants to claim a refund after the period, he/she has an option to raise a ticket or visit the resolution center. But the buyer will not be able to get any refund.