Unable to add iTunes TV episodes to Up Next

On my AppleTV device, running TVos 18, I can no longer add an iTunes episode to "Up Next", nor can I mark it to "Watched". I'm not sure exactly when this occurred, but a few months ago I could browse to an iTunes TV episode that I owned, long press the remote and a menu would come up with options such as "Add to Up Next", "Mark as Watched", etc.

Anyone else with this problem and found a solution?

Mike