Vodacom and Afrizon

Last year in around Nov 2017 I received a call from an agent that works for Afrizon offering me a cellphone ( HUAWEI Y8) and a Homemark gift voucher at R389, I remember the amount because I specifically told the agent that I do not want a cellphone that is worth more than R500 but when I received the invoice and statement I noticed that the being charged is R488.99 and the cellphone is a HUAWEI Y5, which I took up with Vodacom and they reduced the amount with different amount each month (from Dec 17 to Mar 18) which I gladly paid. In Feb the amount I had to pay was 478.99, March R488.99, April R484, May R529 and June R549.17 then I decided to call Vodacom again (which I do every month when I receive a statement/Invoice) & try to resolve the issue and they sent me a "Contract" which states that I'm supposed to be paying R483.21 and Vodacom has been sending from pillar to post without any solution. I am really not impressed with Vodacom and the way they conduct business and I will never take a contract with Vodacom ever again.