sony ericsson xperia u (st25i) on o2 -

im selling my xperia u (pink at the bottom), its on o2 and for some reason nowhere has the software to unlock it and i am on vodafone. i was told by the guy at the stall its becasue its so new and theres no software for it. i have lost the plug that the ubs charger cable plugs into but it can be charged from any usb device, eg, pc/laptop/t v/ps3/xbox. PLEASE READ, i can only be contacted by email as i said above my voda sim doesnt work in the o2 phone. i will be on my emails from now on and will reply instantly to any questions or requests. i would really like to sell today so i can go buy a phone on vodafone. im lost without my phone lol