Master parental controls on Xbox One
Xbox One has master parental controls which will override your NOW TV Parental PIN.
If you've turned off your NOW TV Parental PIN and you still can't watch certain movies or shows, you'll need to change the parental controls on your Xbox One to restore access.
Find out how to change the parental controls on your Xbox
You also have the option to change your family filter settings. This will block any images or content that's rated above your preferred settings.