False Sales

Last year MTN was running a promotion for ZTE phone via their contracted promotions company. the sales person told me that the contract will cost me R56.00 a month all inclusive. to my suprice the first debit order was of R250 . i contacted MTN via their FB page and was told to leave my details and they will get back to me. days after a lady called from the promotion Company and told me that the was a mistake and the working on fixing it. apparently MTN is charging its costumers promotion fee. i agreed to wait and see. sec 3rd month it deducted +_1000 cos i keep reversing my debit order this just proved that nothing is fixed and they letting us pay for things we did not agreed on.. i later then Called MTN in January i wanted to pay off this contact because of how things are handled. people from call centre are giving me settlement amount based on the R250 per month that i did not agreed on and that MTN promised to fix. as i type this My credit record will be ruined because of the bad sales that happened that i refused to pay.. Can MTn please attend to this and clear my name i want to settle this stupid account.