Adding to this - I have the same issue.
Every animal my ranger conjures commences combat with my own party (while being controllable) and the only way to fix it is to kill it. Resummoning, reloading save, long resting doesn't fix it.
EDIT2: Update: I've followed a few trails, but confirmed they're wrong. The only thing I can pinpoint is a specific location where it happens. I've also confirmed that it can happen to a warlock's pet.
![[Linked Image]](https://i.imgur.com/ccYcRWm.jpg)