Silverfist drop of book of specialization did not go to inventory

Upon my first fight with silver fist, i killed him and then i died where he dropped the book. When i respawned the book was gone. I then refreshed the instance, killed him again and picked up the book. The book never actually went into my inventory. I tried killing him 3x more and the book will not drop, essentially i did not get 2 passive points which is really frustrating.

my character name is Rum Punch if someone can please investigate?

Best