Duplicate Key Signatures
I know what I'm doing is pretty unusual, but I was marking a score with full of partial transpositions, which appears every few or even single bar(s), to analysis/learn this beautiful peace of music that is attached.
(Additionally I have colored the notes to exaggerate those transpositions.)
In the process, some duplicate key signatures showed up which I cannot remove redundancies. See the bars #15 and #24 in the music attached.
When I close and reload the music, some of them have disappeared spontaneously, but at bars #15 and #24 they persist.