Useless accounts system

I have 2 phone contracts and 1 Fibre contract with vodacom. Since April I have been requesting a cancelation of the Fibre which was processed in May and I was advised that I would pay a cancelation fee which I understand bc I was in breach of contract. Now I look at my invoice which says they owe me money. After numerous phone calls and multiple service requests the issue still has not been resolved and all I want is to pay you guys that money that I owe you. I spend hours on the phone speaking to multiople agents, and then transferred to the wrong departments, just for the line to be dropped and have to start the process from over. At this stage, I refuse to pay you any money as you have had months to sort out the issue and refuse to talk to me. A manager may contact me if you would like to resolve the issue