< how does someone cash a gift card with only the last 4 numbers of the pin >
If my guess is correct, someone tricked you into sending a photograph of the back of the card. They had you cover up the first nine numbers "to protect you" or something like that. The trick lies in the fact that the first nine numbers are repeated in that long number at the bottom edge of the card. You didn't cover that up, did you? So, he gets the first nine numbers from the bottom of the card, and you give him the last four numbers, so he's got all thirteen and sucks the cash out of that card faster than you can say Jack Robinson.
edited to add this photo .... note that the last nine numbers at the bottom repeat the first nine of the redemption code
