The antithesis of customer care

I held a data contract with Cell C that ran into a number of years. I then sold the device and soon after that, made a request to cease services. This is at least 3 years ago. I have now realized that the debit order is still running. I contacted customer services via the website and got no response. I then mailed them and received a call to discuss the issue. I was issued a reference number and told that I would be contacted. Two weeks later I sent a follow up mail. Today I received another call from a soulless customer service employee. Only to tell me that they can’t access my account details because my personal details that I gave them don’t match their system, and there was no way they can help me. So, Cell C can access my bank account every month, but not allow me to access my account, let alone cancel my contract. I am beyond livid.