MTN overcharge of R3,200 but no resolution, explanation or feedback.

The rating of 1 is a very high rating for MTN. I am being overcharged R3,200.00, I am not receiving feedback to my query but ongoing emails notifying me that my query is being investigated (25 days later). MTN has decided to let their outsourced team Summer Mobile resolve my query. Summer mobile does not care and has demonstrated a nonchalant attitude, has not bothered to call me, and responds to my emails requesting more information with attitude. The service received is terrible, and I have spent hours responding to different people on the same issue.