Continuing to get billed after cancel

Hello,

I cancelled my internet service on May 8, 2025. I received an email confitrmation of the cancelation. I continued getting billed well past the cancelation date. I have now called and chatted with xfinity support 5 times. Each time, the agents assured my bill would be adjusted but this hasn't happened. I'm not sure what to do anymore. It has been over a month since cancel date.