Non-refundable不能退款

①used to describe money that you pay that you cannot get back
如non-refundable deposit/fee/down-payment不退还押金/费用/预付款。
②used to describe something that you cannot return after you have bought it

【例句】
At this point, the purchaser will have to pay a 10% non-refundable cash deposit to the auctioneer.
这点上，买家须向拍卖人支付10%不可退还的保证金。

The check-in desks close 40 minutes prior to departure, so if you're late, you're stuck with a nonrefundable ticket.
登机手续办理处在起飞前40分钟关闭，如果你迟到了，你的机票钱便不会退还。