Yes, just dont public that. Its againts rules that you take a gift you already have it. So if this happened again, better not tell the gifter you do that or you could be suspended

Wait maybe we are misinterpreting each other.
As far as I understand your first message, you win it but you gave it to a friend because you already have it. If you do that is against rules, giving a game to someone else. If you do that, then nothing can be done, its like you received the game but in other case if you havent taken the key to yourself or any friend, and you found that you already have the game or dlc just says that you want a reroll because you already own that game. So its the first or the second case?