This happens somewhat often, but usually fixes itself. Usually, I need to save my world multiple times and reload them because they simply sit around and do nothing. Basically, at random points, one or more of my people, any job, will stop everything and stand around, moving a little every now and then. They don’t eat when they are hungry and they won’t go to beds when they are tired.
(tried to put a picture, but it said new users can’t upload pictures, so sorry i can’t explain better)