Bad customer service

I sent a email on the 21st September to cancel my contract. Received a response that my request will be forwarded to relevant department on the 27 September. I was to give them a month notice , came 1st November they but the debit through my account. On enquiry I was told thr cancellation was not actioned. Whose fault is it if they dont attend to thier emails. The cancellation line is never answered that is why I sent email.