Vodacom not processing cancellation as requested for months

This is probably the 10th time I've tried to cancel my contract with vodacom. The only thing the cancellations department is interested in is retainment and not processing my cancellation as per my direct instructions. They continue to invoice me for the full amount despite the fact that my contract was processed as cancelled in August according to the consultant. I followed up over the phone and on Facebook where someone was meant to contact me. It's been 7 days no contact. I want my contract canceled and to have zero affiliation with vodacom as there service is pathetic. I have previously reviewed other service issues with the company which has led me to wanting nothing to do with the company.