Bad Customer service

I have been calling MTN call centre for the past two months to cancel my contract. The agents are so not helpful, they put you on hold without telling you.

Each time i call i am told i owe and its diffenret amounts, i went to the store last week paid R109 because that was the amount on the system i asked the gentleman if that is the correct amount and he said yes are you sure i asked and he said yes.

So what do i do and how do i get help in cancelling my contract?