blackberry 9700 white unlocked xcellent condition fully working but faulty trackpad ?

blackberry 9700 white unlocked xcellent condition fully working but faulty trackpad it clicks but doesnt scroll could be an easy fix for some who knows about phones.its not been water damaged the little sticker by the battery is white and so is the battery.it makes and recieved calls everything works fine apart from track pad which is middle button.im located in hounslow / west london phone comes on it own with 2gb memory card no other accesroies contact 07852822877