Unauthorised contract upgrade

Hi, on 12 December 2019 one of your consultants from Vodacom direct contacted me to renew / upgrade one of our phone packages, I explained that we would be terminating the contract and moving onto a "pay as U go" due to not utilising the current package, the consultant tried to convince me that the upgrade was from U Choose flexi 210 to a 390 contract at the same price or cheaper. I explained on a couple of occasions hat I was not interested but he insisted, I then asked him to e-mail my the offer and I would look at it and consider it. I have now received my latest statement and the account has been upgraded without my permission at an extra R60/month and a once off fee of R149.99. What Vodacom has done here is to **********ly upgrade my package, I contacted the help desk to cancel and they say it will take at least 2 weeks to cancel and only the can I terminate the existing contract, then there is the issue of extra funds that have been deducted and trying to get those refunded