Vodacom Fibre payments

I canceled my Vodacom Fibre beginning of November and I was told November will be my notice month my connection was disconnected last day of November. Vodacom has now debited for December even though I didn't have connection the whole of December. I called and I'm being told that I am paying for my notice month,in my understanding my notice month was November. If December was meant to be my notice month why didn't I have connection. The consultant I spoke to didnt really have answers for me can someone please call me and explain because I am really not understanding this December payment.