Never Take out an MTN Contract

Do NOT take out a contract with MTN. My contract was increased without my consent from approx R1000.00 to R19 135.14!! After numerous phone calls and being jumped between the different departments - their final conclusion is that my contract was always at that rate and they refuse to correct it. Regardless of the previous year's history of payments at the contract rate. They only approved me for a contract of a max of R1000.00.