Airtime and Data disappear and customer care staff is not helpful

My airtime and my data disappeared 3times in a space of 7 days. I called customer care and the lady I spoke to could not give me a proper explanation, not even a statement to say this is what was charged at this specific hour. She was rude and kept interrupting me when I tried to explain what had happened. Even worse, she interrupted me to give me her "maybe's", i.e. maybe this happened, maybe that happened. The staff is not helpful and rude. If you value your airtime or data, don't use the cell c network. The customer care staff won't even help you when you call them.