Hi,
Thanks for info, didn't know about that, but beta testing means the key was generated before the release of the game and it doesn't necessarily means that the game will expire. According to SteamDB that key was generated 3 years ago so it's still full game - https://steamdb.info/sub/187638/

I'm not sure if support can remove individual keys from giveaways so my question is: Do you want to keep this game or should I ask support for help? Btw please check this post, similiar problem with explanation - https://www.steamgifts.com/discussion/pElvz/what-would-you-do-in-this-situation-for-beta-testing#4jrgst0