Vodacom misleading clients

I called Vodacom this morning and till now they have not assisted me, I cancelled my fibre contract with them, called in November to give 1 months notice starting 1 December 2024 till 31 December 2024. The fibre is now cancelled however they still debited me for January 2025. I am aware that Vodacom and all service providers charge for your fibre upon activation therefore you pay in advance for your fibre. I do not understand why I was debited for January because I am not receiving their services this month. I now had to pay Vodacom and my new service provider for the same month. I asked for a manager to call me, yet still they haven't called, Why is Vodacom *****ing customers money, charging for services they are not providing. Aslo dont trust vodacoms month to month contracts, because I tried to cancel with them after a few months and they said I had to wait 12 months or pay an excessive fee for cancellation, so i waited till 12 months to cancel, and now they still taking my money after its cancelled.