over billing of the acount

i have open a contract with mtn menlyn in October 2013, for two TopUp phone tablet and S4 galaxy. the sales person activated the open contract for the other sim card contact number *** which we did not agreed upon, i went to the shop the following day to solve the problem, and i have been told that the problem was solve. to my surprise the problem was not solve by that month end i went to the shop several time and i was premised to be refunded the money that they were deducting but that did not happen until i personally counselled the stop Oder. now i have receive a call saying i have been blacklisted. please help me to recover my money and i want out of mtn other network might be better. my email address: [Email Removed]