Poor Service and Can't close an account

I have tried to close my account for over 4 years, they have been billing me for 4 years and have not used my account. currently owning R 46000 for an account I haven't used. I have been transferred between 4 departments today and each department can't assist me and needs to transfer me to someone else!! Its very poor from FNB!! Will definitely move all my other account away from them!