Have you also verified and set the Album Artist tags?
If you did that, you also better stick to these rules:
- all files must be tagged with an Album Artist tag
- all files in an album must also be tagged with a track number, on multi-disc releases also with a disc number (different tag!)
- all files of a particular album must be tagged with the same Album Artist. (the regular Artist tag can be different for each track)
- more than one Album Artist is not supported. Try to use Plex like that, and you will get chaos.
- all files must be in a folder hierarchy like this one: https://support.plex.tv/articles/200265296-adding-music-media-from-folders/
That includes sampler albums and compilations as well! - The Album Artist of compilations is usually “Various Artists”. Ensure that all albums tagged with this Album Artist name are stored inside a same-named Artist folder (in accordance with the above linked folder structure)
- all albums which are stored inside a particular Artist folder must be tagged with the same Album Artist name
To achieve the above, I urge you to use a dedicated meta tagger software. The Windows file explorer properties dialog is insufficient.
Peronally, I use mp3tag
After you have checked and corrected your files according to the above, perform the Plex Dance light with the affected albums. (“light” meaning you can omit step 4)
