New unbranded unlocked bold 9900 NOKIA LUMIA 800 BRAND NEW BOXED ON O2 FOR SALE !

hi everybody, want to sell my NOKIA LUMIA 800 MARKET PRICE ABOUT £400 POUNDS and wants to sell in £ 320 already got Iphone so its an extra phone want to sell. I have all the accessories along with the phone brand new scratch less phone on O2. dont know if you can unlock it or may be keep using on O2. THANKS for your help i have attached a link from you tube.