When I try to activate this code I'm getting the message "The product code you've entered requires ownership of another product before activation. If you are trying to activate an expansion pack or downloadable content, please first activate the original game, then activate this additional content."

Pixel Puzzles 2: Space isn't DLC, so I'm not sure what is happening here. Is it possible this key is for something else? Regardless, I can't activate it.

I'm getting the same error with the new key.

Okay, I tried searching the discussion threads for the game and found this: https://steamcommunity.com/app/355920/discussions/0/4034724270488559030/

It turns out the last post is correct, the free Pixel Puzzles Ultimate needs to be activated first before the code for Pixel Puzzles 2: Space can be redeemed. I wish the store page made any mention of this, there's no warning or anything.

Anyway, I got the code activated and marked it as such. Thank you!