1st time post but have looked through forum for an answer which has resulted in a dead end, Current issue majority of files added to library are not picked up on scan, some do make it in though. If i copy of the contents off to another location and copy it back in the file(s) are detected and added to the library.
Try…
Flight of the Navigator (1986) [Bluray-1080p].mkv
Flight of the Navigator (1986).mkv
Flight of the Navigator (1986) {tt0091059}.mkv
Additional file information needs to be put inside square brackets.
That tells Plex to ignore all of that information. Otherwise, the scanner thinks that’s part of the movie title. It will not scan at all, get matched incorrectly or get matched as a duplicate of another movie you already have.
I don’t know if this is 100% your problem. I’m not sure why it wouldn’t match then match ok if you move it out and then add it again