Poor customer service

Couple years ago started a contract with Vodacom and it took them a week to sort out my phone after I already picked up the phone just to find out after a week of struggling they put in the wrong SIM card. Went for an upgrade now and I specifically asked the consultant is it the data contract or device that is due for upgrade she told me both need to be upgraded so I chose my device and signed the contract and she said this is just for the new device and data contract. Then they send me the invoice and I still had a few months to pay on the old device after I specifically asked the consultant is the device upgradable or just the data contract and she said no extra payment on old device. Now I need to pay R60 more per month on top of the new contract fee.