@YouTube there is something wrong with your app. I can't shuffle and of the videos in playlists I have, and the repeat button works only half the time. I've uninstalled and reinstalled, nothing helps. Please look into it, because it was working a week ago.
Thanks for trying those steps. Please send a feedback report directly from YouTube: https://yt.be/help/a4gp . While every individual report may not get a direct response back, we do review everything and use the details to investigate and fix issues.