I have 2 Roku devices one connected to the TV in my bedroom and the other connected to the TV in my living room.
I use NOW TV on both devices. I am allowed up to 6 devices on my NOW TV account.
The problem I am getting is that when I log on to NOW TV on a new device that device is added to my device list, but every time I use the Roku in my bedroom it is picked up by NOW TV as a NEW device, this causes my device list to reach the limit of 6, so the next time I go to use it I am prevented from doing so because NOW TV thinks it is a new (additional) device.
I have disconnected the Roku stick in my bedroom and do not get any problems using the one in my living room, so it does look like it's a problem with the Roku Stick.