mtn take more money as what i signed for

Good day<br> <br> MTN has been deducting more money that I have signed in our contract.I have 2 contracts with them and they deduct R300 to R400 per month. I have complain to the store and they should have paid my money back in 7 till 14 working days and they didn't. went back to them them more than twice, I have phoned the the 011 number and they told me that I have a open contract with a limit of R200 and that is why they deduct more. I went back to the store and the consultant told me that it is not what I signed for and they must give my money back. but now again I must wait 7 till 14 days and that is not fair.It is almost the end of the month again and they are going to deduct more again this month. When is this going to end!!!!