When a bee tries to leave a nest it might immediately return to the hive (existing for only a few frames); and repeatedly do so.

This bug is inconsistent as it's still possible for it to leave; if you silk touch the hive and place it at a new spot; then the bees manage to exit, behave as normal, enter the hive and are trapped again.
Additionally sometimes the bug goes away for specific hives.  One hive will let it's bees escape, while the other traps them.