I have the Sims 3 and an expansion pack--Sims 3 Ambitions. Ever since I got Ambitions I've been using that disk to play on. I haven't played in a while and have lost the Ambitions disk but still have my original disk (Sims 3). Every time I try to start my game it says "No game disc found! Please imsert The Sims 3 Ambitions game disk before proceeding". What do I do?