When I want to listen to J-pop I play the J-pop mix made for me by spotify. Now recently it has been adding k-pop songs to the mix. I like k-pop but when I want to listen SPECIFICALLY to J-pop I don't want k-pop songs mixed in.
I assume there is no fix for this except for hiding songs in the mix which, contrary to what the popup message says, also hides the songs everywhere else. But I'm open for suggestions.