Incorrect prices

I have a sale at the stage where the buyer has sent money and is waiting for shipment. I used the feature to set card prices at 95% of market. 2 cards were incorrectly priced by deckbox: a beta plain and an unhinged goblin token.  I'm losing about $12 for these two cards. A third card I priced incorrectly manually. I'm losing another $10 or so on that card (just typing too fast and not being careful). Do I have any recourse? Am I stuck selling at the prices that were posted?