I Can't Register The Sims3 Monte Vista

I'm having the same problem as everyone else trying to register the game, the pamphlet only has 16 instead of the usual 20 character key. I see some people had to enter in the key when they installed it however, I wasn't prompted for it and I also do not see "Monte Vista" as an option in my list of towns.. I generally stick with the world adventure towns, but the games were on sale so I decided to try buying a new world.. What gives?