CHARGED FOR USSD NOT REQUESTED

I have been charged R1266.90 for content services & USSD on data contract *** in May. I have called customer care 3 times & I have been politely told that this is not Vodacom's problem and I must contact Load a Buddy which I have done. They have informed me that this is not a subscription service but a USSD service that transfers data & airtime to other numbers which means someone was purchasing 100MB data bundles through our data contract somehow. As this is through USSD this is not something that Load a Buddy is responsible for. Most if not all of these bundles were transferred on 15 & 16 April. My wife and I are the only ones who have access to the modem and we have never heard of this service and don't know how to do USSD from a laptop. The sim card was also not working at this stage, we thought it was faulty & did a sim swap on the 18th. Due to this we suspect foul play & as this appears on my VODACOM invoice and VODACOM has deducted the funds I do feel this is VODACOM'S problem and insist that this matter be investigated and monies refunded or I will be reporting the matter to the National Consumer Commission. You can contact me on *** or my wife on ***