MTN profitability

I must compliment MTN for finding yet another way to reward their stock holders. Recently I had been without electricity for over 36 hours and needed to take action to save the contents of my deep freeze. I made a call while rushing around the house getting ready to collect a generator. The call was ended and my call register showed the call taking just over 5 minutes. MTN, however, claim no end of call was received and thus depleted R180.00 airtime I had just purchased. The implications of this is when using your cell phone on the road any loss of signal to the network will allow MTN to charge the total of all airtime you have. Their system does not recognise a dropped call. A major engineering flaw in my humble opinion.