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Strange, all you should need to do is drag the files to the iTunes / Music App icon.

Or File > Add To Library or File > Import

If that doesn’t work it could be something wrong with the files you’re trying to import.
 
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Reactions: MisterSavage
I keep the "Automatically Add to Music" folder in the dock. Find it in the "Media" folder. Drop files, or folders, onto the icon, or open the folder and drop stuff into it.

Mine is here:
/Users/me/Music/Music/Media.localized/Media.localized
 
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