This is less of an issue if you judge everything that isn’t first hand from a known friend or family member as suspect or at least just a waste of time. Facebook used to be a place to talk to people you knew in the real world. You could ignore anything they reposted and still engage with the actual examples of their own experiences that they posted. But now it’s so flooded with ads and listicles and clickbait and video clips that it’s not even worth trying to keep up with the people you actually know.
It might be similar to a song you’ve heard but you’re misremembering the notes of the existing song.
Maybe try playing it for an app that recognizes the song that’s playing and then listen to any songs it guesses might be the song.