Telkom billing for suspended services

So Telkom have suspended my service, they refuse to cancel it and are insisting that I have to pay before they can cancel. I want to avoid charges accumulating while I pay back what I owe. But they keep billing me each month for a suspended services. How am I supposed to ever catch up. This is not ethical. I am not on a contract. I dont dispute what I owe them. But this is predatory.