it just gave me the original :(
That's weird. :/
As Dan mentioned above, you should try contacting them about what happened. They'll be willing to help resolve your problem. Because if you purchased Universe Sandbox 2, but didn't get the code (which is a weird glitch that happened), then Giant Army should be able follow through with getting the right Steam code to you.
Give it a try, you really need to check out this simulator, there is nothing else quite like it. :)