Can't proceed to the end game after defeated doryani (act 6)

I can't proceed to the next level of the game which is the "end game". I'm still stuck on the act 6 or what it is called in the game is another act 3 but in red title. When I defeated the boss fight on act 6, the game told me to talk to doryani in the ziggurat encampment. Unfortunately, when I went to talk to him it seemed like nothing happen and I was unavailable to go to the next level of the game which was the "end game". Please help me because if the game can't play like this how would I go to grind and grind and sell more things ayy.