Logging out of devices on NFL Sunday Ticket App - DirecTV

I recently installed the NFL Sunday Ticket App on my phone. I watched it at some friends houses on their television devices the first few weeks and now I'm trying to log on at home it tells me I need to log out of a device before watching on my device. I have no idea what device I'm logged into. I called customer service and they have no way of knowing what device it's logged into. I need to know what device it's logged into so I can use it! This is unacceptable not to have a device registration so you know where you are logged in at or be able to force log out of a device.

This question, "Logging out of devices on NFL Sunday Ticket App," is about DirecTV channels, programming, equipment, and sports.