Lowsy Vodacom Client Care !!!

I need help in understanding what it takes to cancel a subscription with Vodacom!!! I have been trying to cancel my data subscription for 2 years now, and they continue to just take by debiting my account every month - they make it hard to contact them , you cant even send an email - if you lucky to speak to a constant being in hold for ages - they have no clue how to assist you. This must be a crime!!