Question about contest winning

This may be an overly convoluted question, and I'm sorry if it's been asked before. Some time ago, I entered a Dota 2 contest. Before the contest closed, I received a copy from a friend, and sadly, didn't think to remove my entry. Now, the contest has closed, and I've been notified that I won (no email has arrived yet). Since I already own the game, there's no point in accepting the gift, and depriving another member of the community. What's the best way to proceed? I'm sure there's some form of standard protocol that I should be following, but I'm not sure what it is, and couldn't find the answer anywhere else. Any help would be appreciated.

Thanks in advance.