CROWBELL becomes invulnerable and cannot be damaged to progress the boss fight

2514205472

During boss fight the NPC becomes invulnerable and stops the progression of the fight. This has happened multiple times. I have exited to the character selection screen and out of the game but return to the same bugged encounter.

I had the same problem today. Playing on xbox. Tried logging out and switching characters and still this boss was invulnerable and untargetable.