Vodacom imposing expired contract and refusing to canel it

On my contract I had two numbers . I requested cancellation of account .

Vodacom only cancel one number although I forwarded every information they requested

Yesterday I contact them , I was told to phone retation and cancellation . I phone them today I was told to phone the billing department . Vodacom keeps on shifting the poles . I do not know what to do any more as there do not have ombudsman. The phone number they are refusing to cancel is lost I am forced to pay what I am not using . When I phone requesting them to BLACK list the lost number they refuse as according to them is owing .