Refusal to sort out their own mistake

When making a purchase, I pressed the back button to add a tip, but the app read it as "Go" & used the wrong credit card - company card used the previous day. I immediately called and cancelled the order, explaining what happened, and that I had to use a different card. They said that a credit would be issued, and that I can request it to be refunded to my boss's card. I then re-ordered, using my own card details. BUT THEY USED THE CREDIT INSTEAD OF MY CARD!!! And now say there's nothing they can do.