I have two movie files, for different movies that have got attached to one movie. I have provided an image here
How do I split these to map to two different movies?
Name the files with the year of publication (according to the Plex naming conventions), like that:
Harry Potter and the Deathly Hallows Part 1 (2010).mkv
Harry Potter and the Deathly Hallows Part 2 (2011).mkv
If that does not solve it, you may use the context menu options in Plex (when logged in as administrative user) and choose the "Split apart" option.