Soft locked

act 3 cruel difficulty.
Got stuck after I killed the Jiquani's Sanctum boss, I picked the soul core but don't have it in my inventory. When I go to the altar at the Infected Barrens, my character does the animation to put it on the altar but nothing happens. My character is locked at this point and can't progress any further.
Went back to kill the boss again to see if I get the item, it doesnt even drop.

bump, because I cant even play the game anymore after soo many hours of the campaign, I cant even complete it