If so, I would say try doing a “Refresh all Metadata” to the shows/libraries it’s affecting. If not, I would say it might be something with the Samsung TV app, maybe try uninstalling it and reinstalling it.
The only other thing I can think of is maybe there’s database corruption, but I don’t think I’d go that route yet. However, if you search google for “Repair Plex Database” it should give you a guide on how to do it for your particular operating system. Again though, do this as a last resort.