This isn't the first time this happened, This kept happening to me throughout the day.
Basically what happened is there was a cyclops up against the wall, and I was running towards it to attack it(by pathfinding), and my character went past the cyclops as if i was trying to attack it from the other side, but since there was a wall, I got stuck.
Sometimes i'll be attacking a cyclops and he wouldn't attack back(for a brief second), so my character would end up following him, and eventually through the wall again.
This might be caused by the new pathfinding that was recently put in? It might not be. Hope this helps.
