Vodacom ***** *****ing from customers

Good day. Please beware of vodacom agents.... I have just realised that i have been ****, mislead and vvictim of theft by vodacom. In July 2020, i had a vodacom agent and still remember his name, Zein call me telling me that vwith this whole pandemic they are wanting to help customers save money and change my plan where i will be paying less. Instead of my subscription of R578 i would now only pay R390. What a load of bs lies i was fed. Now in December was the first month i noticed my account been debited for R793,98 which is double that i thought i was paying. I called vodacom customer care to explore the amount I ve been debited for since July and the lady gave me a breakdown of the amount, this was not what i was told when i got that call in July, who gives vodacom the right to go and charge a customer more and mislead customers and now they can't tell me who the person is and telling me they not able to assist. This is ****** ridiculous and theft, ***** *****ing from customers. What do i do????