Disappearing airtime and data

MTN has been deducting airtime and data when my it has not been used. At 11h15 I loaded airtime as I was surprised that I had R0.00 when the previous day there was R26. 00. I still have free minutes so I was not concerned with buying airtime. At 11h30 I got a text to say that my balance had been depleted which was 15 minuts after I had just bought airtime. I also had data so was very surprised. I called the MTN customer care and was on the call for 58 minutes and a supervisor could not even speak to me. It is now 14h26 and I had to buy data as my data now was suddenly depleted as well. Why is my airtime and data being deducted by ridiculous amounts and why when you call MTN is a supervisor not available and things need to be escalated as the consultant cannot pick up why the monies and data is diappearing. I am ever so sorry i switched networks to join this one as MTN does just does not seem to care nor provide feeedback. My reference is 257 581 044. I want a full refund on monies and data that have incorectly been deducted.