Some measures having uneven rests?

Hello. I am trying to transcribe a jazz big band tune with Musescore 4, but while editing parts sometimes measures will appear blank, with no rests whatsoever, or will appear with more than 4 beats of rests, shown in the first two screenshots. Sometimes I can fix the rests just by adding notes and subsequently deleting them, "reminding" the software of the beats that should be in each bar, but most bars aren't able to get fixed. This happens in the director's score as well as the individual parts, which makes it even harder to fix, because fixing the issue on one page doesn't fix it on the other page. This is becoming a big issue since I would like to have a clean arrangement to print out individual parts.

Thanks - M