xfinity TV set Box is running

My network usage shows that the Xfinity Set Top Box is running even when the TV is off and nothing is accessing the box.  Its eating up all my data plan and I need to get this fixed.  When I called the 800 number, their answer was just to add $11 for an unlimited plan.   The online chat was completely worthless becuase they cant see network usage. 

What are my options???