Just got the game on steam and can't even play it, serial number is wrong.

Just bought the game on steam and it doesn't even allow me to play it, registered my stardock account and activated my account and still can't play, says serial number is invalid. I have try both ways, just by putting the serial numbers on without the - and have also try putting it with the - on the view serial, number screen, Every other game allows me to just play the game from the start once it finished downloaded on steam, i can't understand why this game won't let me. Plus the serial number is wrong, i know i put it the right code 100%.