SHOCKING SERVICE & MISLEADING UPGRADE INFORMATION

I have been with Vodacom since I was 14 years old! I have always paid my bills on time, upgraded every 2 years etc etc. I now have finished my contract and due for an upgrade. I have told Vodacom numerous times that I am not taking an upgrade and want to adjust my contract (to save money). I was offered a uChooseFlexi 230 (which means! R230 per month - thats it!) NOW after being promised this contract I a being told I am going to be paying over R600 per month for this contract (with NO UPGRADE DEVICE MIGHT I ADD) How does a contract go from R709 per month (R540 being the handset installment for 24 months) to not taking an upgrade (NO HANDSET) and just paying the for the airtime instead? If I do not get what I was promsied (which is uChoseFlexi230 paying ONLY R230 per month) then I am cancelling my account with you guys completely! Dont promise things you cannot keep! Not once was the confirmed new contract emailed to me (almost as if you expected me to just accept it and then get smacked with basically the same bill I have been paying for 24 months) I want this new upgrade of R600 to be CANCELLED and the new contract of R230 per month ONLY emailed to me to be confirmed in writing!