iveco daily 35c11 rear disc pads 2000 modle?

hi, i have had the rear pads and handbrake cables replaced , but the handbrake is useless, it works slightly when going forward,but nothing when rolling back,also when i pull it up it seems like its on then it will roll forward a bit and then pull up 4 more clicks and work slightly,my friend fitted these but dont know why it wont work, can any one please help, thanks for your time , harry.