POS tried to deny it as having already been returned. Some TL (not somebody I know, but I've been away for a while) told her the over-ride code. The first transaction, apparently a receipt didn't print so she assumed it didn't go through at all and ran it again. The second time, she told it to give cash instead of going to the debit card, but the drawer wouldn't open. So then she switched to another register to process it yet again. The second time, I was halfway paying attention (still helping my own guests), and when the drawer wouldn't open again and she got the "item already refunded" page, I stopped her to call for GSTL. But he was with another guest and that other TL who I don't know told us to just move to the other register again and override to make it right, and then to reboot the first machine that wasn't opening up.