My new run is an Eldritch night pretty freshly level 3. Last night I thought attack of opportunity was behaving weird... not triggering.
I also noticed something similar to what you describe where I seemed to lose an attack? I was walking to an enemy and stepped in acid and never saw the attack go through. Couldn’t find the roll on the action list. My animation was also stuck mid way through an attack which made me more sure it was a bug.
I haven’t played a ton of the game so I wasn’t sure if there is some system understanding I was missing that was preventing me from taking the AOO?
Similarly I get confused about when and why the True Strike effect is removed.
The problem with early access is not knowing when you’re simply misunderstanding a subsystem or it’s not working as intended. But hey it’s a problem I signed up for