Bots have stopped working, and also, most of the 7 codes are now used, people were using bots that the skittles promo glitched and sent duplicates of codes. No the codes aren't unique, they are duplicates so it means they can be used at any time... I bought codes of 2-3 sellers and some of there codes were Turing out to be used. This has happened to everyone, so when you buy codes, at first they will be unused, but as there duplicates, at some points someone will use them... I have stopped buying and selling these on ebay, and so has quiet a few people, as you have to replace their used codes, therefore going in a loss, but trust me, codes have been duplicated, the seller of codes are screwed...