Seems to be a combination of a spelling mistake and a lack of responses. I sent a payment to the address the seller requested. Just that it was spelled wrong in the PM he'd sent to me. I followed up with a payment sent PM but got nothing in reply. Nor to more than one inquiry on the order status.
Now, I can appreciate when a bargain sells out quickly, but to have missed out on the sale due to the seller's spelling errors, that sucks. To not get any timely replies to the order, well, that sucks more.
It would have been nice to get a reply early, I could have shopped elsewhere for the cards in the meantime.