BAD CUSTOMER SERVICE/CARE

I've been a customer of Vodacom since 1996 and never in the 28 years have I seen service as bad as this. Since December 2021 I've been trying to cancel a contract with no avail. I called them in December 2021 (and as usual the conversation was recorder) to cancel this contract (this contract was at that stage 22 years old). After answering all the questions I requested the cancellation, the agent confirmed that the contract will be cancelled March 2022. Then all of a sudden I get letters, emails and phone calls from Vodacom stating I owe them money for this contract. I told them it was cancelled and it is recorded (their response, that means nothing), I send them an avidavit, no response. If I knew this will happen I would've continued paying this contract, no I owe them nearly R8000. I am a pensioner where am I suppose to get that from? Vodacom you should be ashamed of yourselves. No customer service or care for that matter.