Refund on overcharged account

<p>Ever since taking out my MTN contract in January 2016, I have been overcharged every month. I am supposed to pay a fixed amount of R100, but they debit over R1300 from my bank account. It is a constant battle for them to give me back my refund. Last month I removed my simcard and stopped using it, but they still charged me R1300. I have been calling them for my refund since 01 May 2016 to no avail. I call every week and I am promised to be refunded within 7 days but I have received nothing. When I call back, they tell me that they dont know what is going on with my account. No one is assisting! I even went to the branch were I took out the contract and they also cant assist... and they still have the decency to send me the June bill!</p>