CONTRACT CANCELLATION - USELESS SERVICE

My contract ended on 24 September 2019, contacted your cancellations department on 1 October 2019, spoke to Nomcebo. Advised her my last installment has gone off and I no longer require the contract as i am unemployed, she tried to retain me and offered me a 40 something rand product and I declined as I mentioned I would not be able to afford it. She said ok, and she would cancel and an sms would be sent to me regarding the cancellation and 8 days later, no SMS was received. to my surprise yesterday i receive an invoice and a statement stating come month i will need to pay R220 for the airtime i used to get as per my expired contract terms. I contact your call centre again and ask them whats going on, the agent said no if i do not contact you guys in September then the contract will be extended to october, mind you the automated system before i get to an agent states that the contract has ended and im eligible for upgrade and not obligated to upgrade. Comprehension and understanding are clearly weak points with your agents. Where in the contract that i signed did it state that if i do not contact you in september and contact you a couple of days after expiration, that the contract will auto renew or continue against my consent for the additionals (airtime) i used to get with it?????? and the agent i spoke to today, Shavon - has the audacity and liver to say it is my fault that Nomcebo did not do her job properly. I asked twice as I was baffled and then he only realised what he was saying a couple of seconds later. This is a clear indication that they do not want to LISTEN TO WHAT YOU ARE SAYING AND JUST WANT TO RESPOND!!!!!! When i started stating facts of how Nomcebo offered me the 40 something rand product then he was like ok no i will cancel your contract immediately. I have requested a call retrieval to be done as I am not paying for any airtime I did not ask for, your agent said that is my problem if i don't pay and yet its Vodacom's fault that you have poorly trained agents who act arrogantly and cannot do their job the first time around. To say I am shocked and baffled is an understatement, i told that agent i will not let this go and i better get a call to resolve this. He agreed and told me his supervisor is not there and will escalate to Nomcebo's leader. I am NOT PAYING FOR ANYTHING - YOU ARE TAKING CHANCES, not with me.