Terrible service - going in circles

I have a data only sim only deal which expires 3 March. on 25 Jan I was called and offered an upgrade to a SmartData 5GB TopUp deal at the same price I have been paying for last 2 years. I received a contract stating that the cost is R215 with a discount of R135, which brings me back to the R80 I was paying. I received the invoice for Feb stating that not only had the "new" contract begun on 25 Jan, but I had been charged for it at R215. I have called customer care to try to sort it out but have had no luck. It has been escalated more than once. I have had sms's stating that the issue has been resolved, but no-one has managed to resolve it. When I tried to cancel the contract I was told that I can't yet because a new deal has been agreed upon. The point it, I am going in circles. I've had to repeat the issue maybe 10 times now, and each time I am told it will be escalted and promises are made that someone will call me. The only call I have received since first contacting customer care was on Friday 12 Feb, and I was told that someone wouold contact me, so someone called to say that someone will call. Pathetic service.