***** on customers

The past few months, whenever we as customers have loaded airtime we have realised that the service provider takes our airtime and we don't get the loaded amount. They claim that give you extra airtime at times which you cannot utilize. Further more if you leave an amount on your phone, tomorrow you will not get it. When balance is checked it is 0. We are being ****** from. My personal phone does not take advances so I am never owing any amount but this happens every time I recharge. Very disappointed.