About PoF Serial Code

i pre-order PoF (Ultimate Edition) and got a game Serial Code in my mail... still when i open game it does and update and dont ask me to enter this code...where should i enter it? Or since i bought it with same mail as my game account it is added automaticly?

You don't enter the code in game. Click on Guildwars2.com (top at the left of this page), then hover over 'services', click on 'My Account' and you will see a big red button that says 'redeem code'. Use that and enter the code they sent to you.