Airtime keeps disappearing

Everytime i load my prepaid airtime , it disappears. I phoned the call centre & i was told that it is because of the internet. And that is ****,because my data switch was off.. firstly i was told that i should contact 1555 for data support to give me a proper explanation of what happened to my airtime. Data support sent me back to the call centre to request for itemised billing.<br> <br> When i call the call centre, i was told that i cant get an itemised billing because i'm on prepaid. Again this morning, i load R5 airtime & buy 20MB from Mtn for R2. Few minutes later, i'm left with R0.01.. Mtn please give me a proper answer, why are *****ing from me?<br> I dont have content services or anything of that sort. I've been with mtn for years & i think its time to port out & still keep my number! Im so ****ed