Bullying tactics and refusal to cancel contract.

So I contacted vodacom at the end of 2019 to cancel my Contract, their *********** contact agents never cancelled it as per my instruction and continued to debit my account. I had to reverse the debit orders and eventually changed banks to prevent them from debiting by account, now nearly three years later I am being threatened with legal action because I refuse to pay what they claim I owe them, it is not my fault that vodacom failed to cancel the contract after I phoned and requested the cancellation. Go retrieve the call recordings and you will find proof that I phoned, spoke to an agent and instructed them to cancel. STOP THREATENING ME OVER NONSENSE AND GET YOUR HOUSE IN ORDER!!!!