Pathetic Service from MTN

I've send MTN a complaint email almost two months back, did not receive any response email to this day. MTN making me pay for something I did not use after their representatives advised me incorrectly. Took out a new contract online and received a device which wasn't working. After being advised by their representatives they issued a new contract, new device and collected the faulty device. Now MTN is making me pay for 2 contracts after they collected their faulty device and sim card.