Non adherence to contractual agreement

I am very heart broken by Vodacom's deteriorating service. Three months ago I took up a migration contract and to my surprise a month later what was delivered was totally not as per teleconversation contractual agreeme. We agreed on 3G nd R65 at a price below R200 as I was long standing customer and I did not was a cellphone contract. What was delivered even to date is R65 airtime at a discounted price of R59 and 3G data was charged at a discount of 20% and I was told my sister added a recurring data. This was later reversed. What they did not fix is the contract we agreed on. To this date no response on my request for investigation and contract recording.