Unfortunately, I have no idea what to do. I've never had this happen with one of my giveaways, and I've done LOTS of them. I've already reached out to the site and emailed them about the situation several days ago, with no response. One thing I won't do is I won't use OtakuBundle for giveaway keys anymore if they can't get back to me to replace keys that are later revoked for whatever reason. I've had 2 other people mention that their key for that particular game was revoked within the last few days or so. Only that game, just the 9 copies I had leftover from a big bundle. It's something to do with whoever provided the keys for that particular game, or the developer of that game being a butt-head. I don't know which.

I sincerely apologize for the trouble. I don't want to get negative feedback for something that is obviously out of my control, but I also want support to be able to remove the fact that you won the game so you can "win" it again and have it in your library. If you want to contact support, that's fine, but please don't say anything that's going to get me in trouble personally. I didn't do it. I pay my bills. :(