Over deductions - Monthly debit order

I was contacted by MTN Direct regarding a special they had for R 79.00 package on Airtime, SMS and Data per month. They ended up deducting R 110.00 per month. Upon calling them several times trying to sort out this query and spoke to a few call center agents who advised that they did not put through the discounted rate and was charging me on normal rate. It's been 2 weeks already and I still had no feedback from MTN Direct. I have a list of names for 5 people that I spoke to regarding this query including the supervisor who promised me that this will be sorted out last week and still I await. It's amazing how they will make empty promises just to keep customer happy when in fact all it does is make us further unhappy. One of the call center agents I spoke to said that it takes a while to get a response because they have a backlog of these queries, Hello MTN Direct are you always in the habit of incorrect billing that we have to wait this long for feedback. I rate MTN service as extremely poor ? <br> <br> Regards <br> Ramona (Very Unhappy Customer) <br>