Vodacacom Cant cancel my contract

I took over the contract from the previous employer so that the contract can be on my name. so I received the premature quotation, i paid on the 17th Jan 2020, and emailed the proof of payment, signed premature quotation with ID copy attached on the 23 Jan 2020. I have called both Collections and Cancellations department, both of them can't cancel my contract. I have been calling them since the 17th of Jan 2020 until to date yet I cant be assisted. Can i please get help to get this done once and for all because they are taking advantage of us as customer??