Watchlist - Included with Prime Video

When I check my created or rating lists on IMDB, It shows which movies are "included with Prime" (see the attached image) so I can watch on Prime Video, conveniently. This is a perfect idea thank you! But it does not work properly for all the movies that is available on Prime for some reason. It also does not work at all for the "watchlist" list which should be the first place where it works.