Cannot access TV+ on my Apple TV (3rdGen) - stuck on "Accessing TV"

My Apple TV 3rd generation shows available Apple content across the top of the home screen when the Apple TV app is highlighted. However, when I select the Apple TV app it will only show “Accessing TV” with a the spinning wheel. I have signed in and out of iTunes and iCloud. All other streaming apps work fine so this is not a connection issue. Why won’t the OS resident Apple TV app work on the 3rd generation Apple TV, model A1427 ?