I cancelled but no email confirmation after 2 days-now I see another bill

I cancelled my internet on Oct 31. have cencellation number. I have received no emails confirming the cancellation, as I was told by representative on the phone. Now I see a new bill for November. I tried to call but no luck. How can I confirm that I am going to receive the bill credit that representative gave and I will not be continued to be billed for service?

Thank you.