I WAS BEING CHARGED FOR 12 MONTHS WITHOUT USING THE SERVICE

long story short before switching to xfinity NOW, i was using regular xfinity, JANUARY 2024 i switched to xfinity NOW, i cancelled the service, and the agent told me IT WAS FOR SURE CANCELLED, so i have no service with regular xfinity anymore. But i was still being charged every month for 12 MONTHS, what can i do about this, i tried customer service, they told me to CALL billing team for help, and the billing team told me to CHAT to customer service for help. i need to press charges. GIVE ME MY 12 MONTHS REFUND