Billing issue

I cancelled everything that I have with Xfinity except for internet two months ago. The bill arrives last month, I was still being charged for Netflix (suddenly 3x the previous amount) and a piece of equipment that I had turned in with the tech. 
I called Xfinity and had Netflix removed from my account and also the piece of equipment that we returned to the tech with all of the other equipment. (*This piece of equipment is no longer used by Xfinity and hasn’t been for many years. It can be purchased at a store for $10. Xfinity is charging $14 per month.) 

The bill arrives this month and guess what? Netflix is still there along with the equipment charge. Several people warned me that Xfinity will try to scam me when I reduce my services. What can I do?