Unfair deduction after a contract ends

I have been paying money for a ended contract as from September last year when you call all they do is give u reference number and ensures you that the deductions will stop and nothing happens. Worst of all instead of cancelling they deduct more .I won't recommend them to anyone Vodacom and other network companies are way better .it irritates hence they called to offer their services and now when it matters they refuse to help.