Where is my airtime and data going to ??

I thought I had lost my mind when I saw my airtime and data disappearing minutes after I recharged!! That is until I saw many complaints on this forum and from friends to say they had the same experience. I'm a pre-paid customer, I switch off all my apps and only switch on data when I need to use it....but in the last few weeks as soon as I buy data it disappears and my airtime without even making a call!! <br> This is ridiculous and costly...I'm going over to Cell C