Xfinity charges after account cancellation

I requested my account and services to be cancelled about a month ago through customer service representatives over the phone and also online a few weeks later. I received a confirmation email and ticket numbers. They have not yet cancelled it and my account is still being billed. I’m going to have to go in person and make a scene or sue them as I don’t know what to do with the outright deception and theft. I urge anyone who has any alternative alternative option to not become involved with this company.