I just bought the game and installed in and entered the serial key correctly.
When I will try to play the game it asks me for the serial key again.
I re-enter but it keeps asking and asking and a type it correctly.
wait when u enter ur serial key there , its must show u some agreement to click it yes n processed forward , than there u can choose ur username and login information. but if there is nothing like this , than im pretty sure some one has used that key already ..... you should contact EA support on phone if u frm USA or the shop from where you bought the game . Good luck . daniel