Money taken without use of Cell C service

I would like to report an incident that caused me much worry. I am a Cell C user and have enjoyed being a loyal customer. <br> <br> Unfortunately, two days after my last recharge of R35, my balance was R0 even without any use of the internet, calls or sms. The only purchase I made was that of a R5 monthly Whatsapp option. I only used my whatsapp after the purchase.<br> <br> I believe it is illogical for the rest of the R30 to disappear from my balance. I really would appreciate an explanation from the company about this issue.<br> <br>