Can't find my new content (old files are OK)

Server Version#: 1.18.0.1913

PLEX finds all my old TV and FILM files, no problems at all. But the film and the two TVseries I downloaded and added will not show up in PLEX. Then updated to latest server version. No change.
These are mp4 files and I have named them just as all the old ones, never had any problem with finding content.

Windows 7 on my PC and all files on my Synology DS214PLAY, used it for many years.

Please, anyone can help? Cheers