You bought the key, you typed it in, but Steam or the game launcher is rejecting it. Don't panic. Here are the most common fixes.
Every empire began with a blueprint and the keys to the site. Are you ready to build yours? Construction Simulator Activation Key
The "full story" of getting a activation key involves choosing the right edition and platform, as the franchise has several iterations (most notably the 2015 and 2022 versions). 🔑 How to Get and Use a Key You bought the key, you typed it in,