Vodacom - Lack of cancellation of contracts

I am extremely disappointed and upset with the service I have been receiving from Vodacom South Africa. I upgraded to a Vodacom Fibre deal and I have been trying to cancel the LTE contract that i was using before. I have been phoning for 3 months consecutively and the contract is still not cancelled and each time a different service provider assists me and they tell me that they have cancelled the contract and they will send me an email to confirm cancellation. I have been paying for a product that i am not using for the past 3 months and in this difficult economy, this is exploitation. Vodacom needs to hire competent staff members who know how to cancel contracts successfully. This is extremely upsetting and something must be done about it.