Hello steam1gift.

Switchblade is tagged as "Profile Features Limited" on the Steam store. Games with these tags are not properly reported as owned by the Steam API. Since the site doesn't know who owns the game, it won't let anyone join giveaways for the DLC.

The only solution, at the moment, is to wait until that tag is gone and Steam starts properly reporting ownership of the game.

Hello Zomby,

Thank you for your reply.

Good to know this.

Have a good one.

All the best