Music disappears from piano staves

I have been revising my piano concerto recently and all of a sudden all piano music, except for the little portion I was working on disappeared from staves. I’ve tried the trick with “start voice” “end voice” in the editor, but it’s not that. No music, no rests…nothing. I’ve noticed when highlighting some of the notes in the score that “force duration” is suddenly on, but I don’t understand a connection between the two. I simply selected everything in the score and disabled it, but still no music and no playback.

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