Bug: Act 2 - Rathbreaker fight

I was fighting Rathbreaker and got overwhelmed with monster, so I ran down them small hill from where he starts.
When I got down the hyenas kept coming out of the dens and the Rathbreaker was just standing still on the post where he starts. He didnt take any damage or moved.

I had to start a new instance.

I tried to get back to the town with a town portal and then return, but that didnt help.I