Hard to say, may have been done by another software and used ID3 genre id instead of name.

Thanks. Your recommendation fixed the issues. But, I am curious how these "fake" genres got created.

You can try Tools > Edit tags > Update tags on those files.

App version: 2004.2
OS: Windows 11 with all updates

I have about 29K tracks in my library. For about 100 tracks, when I view the file properties in Windows File Manager, the genre is different. I see the following genres: 32, 0, (0), 8, (8). All the tracks within each of these genres are of the same type. e.g. All the files under genre 32 are Classical. When I view the track detail in MM, they all look fine with correct genre. See attached screenshots.
[url]https://www.dropbox.com/scl/fi/3x6ctfjwp0rl8a1ajjlga/Screenshot-1.jpg?rlkey=w11hjdooi2cizqywl0yd7w8vt&dl=0[/url]
[url]https://www.dropbox.com/scl/fi/jf5jl5ofy0pbg9ncbr7vz/Screenshot-2.jpg?rlkey=oefzfmjpweuo20cszras3k1xy&dl=0[/url]

I then edited the genre in MM to something different and then changed it back to the original genre and the problem associated with that file disappeared. Seems like I need to fix all the other 100+ files.

Need your guidance on how I can resolve this. Thanks.

Murali