Vodacom - cancellation of contract

I have a contract that is over 36 months old. I recently received a call for an upgrade on one of my contracts and so I informed the person that I want to cancel my contract which is over 36 months old. Subsequently I received notification that I have upgraded , sim only, as i am continuing on my contract without a new device. When i checked my contract status on the Vodacom.app, this month, I saw the contract which I cancelled over the phone was still continuing to the tune of R399 p/month. So I phoned the Customer Csre Number and after nearly 40 minutes talked to a consultant but he informed me that the consultant handling my upgrade **** to me by saying he will cancel my contract. I was advised to contact the Cancellation department, but on two occasions the consultants spoke to me for less than two minutes and put the phone down. So I am at my wits end . I just want the 076 contract to be cancelled as it has a financial impact on me.

Please assist. Thank you.