I cancelled my service, never got the adjusted bill

I cancelled my service with Xfinity and returned my equipment promptly. When I cancelled, the representative on the phone said I would get my final bill adjusted if I paid for the full month. I paid on 5/15 for the full month, my service ended on 5/22. I never got an adjustment, and I still got a bill in the email saying I have my monthly bill due on 6/15. I don’t even have access to my account now and cancelled my auto pay before losing it. Please assist.