MTN bad service

I have taken a contract with MTN during mid August of which would cost me R369 a month for 24 months and I would get 15gig anytime data and 20gigs night express data , the first instalment MTN debated R 623.00 from my account then second instalment they have taken R 523.00 from my account and they gave me 10gigs of data to use which was for night express only now again I got an invoice from them which says I have to pay R 523.00 , kindly note I called MTN they said I have to go to any MTN store to resolve the issue I went to the Sandton MTN store they reffered me to the store where I took the contract which is the vaal mall MTN store they called MTN and logged a call till today nothing is happening I have not had anything from MTN here is my Reference number for the call I logged 1- ********** 9827 and also after the call was logged I called to check the status of the call and the guy I was online with asked for my E mail and escalated to his boss who has not gotten back to me here is his boss mail address ********** .