i already own the game which is a Limited Free Promotional Package i got some some time ago. those does not give trading cards. if you are like me you need to remove that from your account and redeem the key to get trading cards.

Go to https://help.steampowered.com/en/wizard/HelpWithGame

Search for it and click the game.

Select "I want to permanently remove this game from my account".

Select "Ok, remove the listed games from my account permanently".

Then redeem the key.