CELL C VANISHING AIRTIME

I am on CellC prepaid and for the past two days every time I upload airtime it will vanish without any usage. In the beginning I thought it was because I did not convert my airtime to data bundles (after R50 vanished), then I uploaded again and converted to data bundles, within seconds of being on whatsapp I received no notification that my bundles have depleted but could not chat further. This prompted me to check my balance and to my shock, R35 of airtime gone plus 100mb in less than five minutes. I have escalated this to CELLC CUSTOMER SERVICES and they could not give me the answers why this has been happening, but been given the \we will come back to you after two days"lame response. I tried to upload with a small amount this morning and this is still happening and it's putting me off the network to be honest"