Cell C is *****ing my money

Cell C overcharged me by over R1000 in may. I queried it the minute I got the SMS stating what my charges would be. No one ever came back to me. When I followed up again on it I was told that the workers were in strike and that it was too late to make a debit change, they were going to over charge me and I just had to deal with it. I was then promised a refund for the over charge in may, and to this day I have still not been refunded. Every time I call no one knows what's going on and no one can give me an answer. Now I get another SMS saying that I'm going to be over charged again. I spoke to another consultant now and again he cant give me any answers. He needs to load yet another escalation query. All these escalated queries and now answers. And to top it all off, he was so rude and so condescending to me.