Heading into NBA 2K19, 2K announced that they were going to be making some changes to how Locker Codes worked. In the past, Locker Codes typically dropped for a limited time and unlocked a certain item. Now, 2K has created a sort of minigame that CAN unlock the featured prize item, but also other things like Tokens, MyTEAM points.
So basically there will now be codes that don’t guarantee a prize, but instead unlock a minigame with a chance at different prizes.
NBA 2k19 