Missing Data

Vodacom is really messing with people and their monies, I'm not sure if this is because they believe that they are the best network or what. My data has gone missing yet again. I bought 500mb and it went missing i then bought 250 mb for 7 day this is within 2 days of the 500mb missing, they sent me a message apologizing about the incorrect billing and replaced the 500mb. Yesterday they took the data again this time no explaination is this an incorrect billing again. So they having a problem with billing every 2nd day. Whenever you call to find what is happening no one can give you an answer. Surely whatsapp only wont finish 250mb and 500mb within 2 days. I'm really fed up with this nonsense vodacom is giving us. They dont appreciate us as their customers at all.