Celphone contract upgrade is misleading

I did a contract cell phone upgrade September 2015 with Summer Sun Mobile which is working for MTN for iPhone 6. My contract stipulated that its R259 for 24 months and receiving R200 airtime and 25sms. I am on split billing where my company pays R300 and I am paying R127 to MTN which totals to R427. After several contacts with Summer Sun Mobile and MTN 808, no one is able to explain why am I psaying above what the contract agreed on is saying. for the amount I am paying I am not even receiving data. My previous contract was very good. I used to receive data and I explained to Summer sun mobile consultant that I don't want a change to what I am used too. Candice and Cindy from Summer sun **** to me saying they will retrieve the voice recording of telesales but its been a month now they don't respond to me. I told them MTN said they loaded wrong contract and they need to change but they send me back to MTN saying that only MtN can change contract. This is serious ***** between MTN and Summer Sun Mobile. Both MTN and Summer Summer Sun mobile are ***** and ********. Suprisingly I went to MTN store and they showed the screen of where all my payments are going but Summer and MTN cant.