Terrible service

I used to upload airtime every month to my cellphone in order to purchase a data bundle for the month, however the last 3 times I uploaded my airtime and try to purchase a data bundle (immediately), R30 or more of my airtime would somehow dissapear..so after this happening 3 times in a row and struggling to get to the MTN customer service line, I just switched to Vodacom and spared myself the frustration each month. Eventhough Vodacom is a little more expensive each month, I will gladly pay it because I know that they won’t ***** my airtime. Thank you for the excellent service MTN..keep it up ??