Billed without authorization

I queried a matter with Vodacom 3 weeks ago about being billed for content services which i had not authorized against my contract phone. i was informed that this matter would be escalated and was given a reference number. i followed up on this matter a week later and this was again escalated with another reference number. i followed up again on the third week and was informed that there was no trace of the previous reference numbers even though these were sent to my phone via vodacom sms. to date i have not received a response and will be stopping debits until a resolution is met.