Can you be more clear in your issue?
It looks like your friend marked a movie watched multiple times or maybe had a duplication error in a sync with an app or media center. This is probably easier to deal with a support ticket with links and more details from your friend.
That is highly unlikely. No one is going to watch the same movie, multiple times at the exact same time. This is consistent with a few other people. Common sense, it is not an isolated issue. I don’t see how creating a ticket would resolve anything if there exist an obvious bug.
Creating a ticket gives us specific details and accounts to investigate. They can also be assigned, re-assigned, and internal notes can be exchanged. This also gets the issue in front of the developers faster as they don’t always have time to get out here and read the forums.
This is most likely what happened, a connected app is spamming duplicate plays into their account.
I have had this many times where I use Series Guide and Cinema HD I seem to get duplicate watches.
It seems both update that you have watched it and so a duplicate appears in history (same time, same date).
What I do is check my history and at the top it shows number of Items and Plays. If these do not match I then select either Movies or TV Shows from the drop down list and then filter by Most Plays. Then delete the duplicates.
Nightmare first time of doing as you may have a lot of duplicates to delete but if you do this on a regular basis it is easy to keep clean.
Just a thought/solution that might help you with duplicates.