Quest: Legacy of the vaal

Account: Gorillson#2988
Name in game: Kalafka

My quest is on Scene 2 Act 3 Legacy of the Vaal

It asks me to return to infested barrens and activate the stone altar.

However, when I return and interact with the stone altar, it only broadcasts the animation but doesn't update to the next step, I am not able to enter Matlan Waterways, either.

I think the quest needs to check the soul cores in my inventory but unfortunately it is missing and I have no idea when and where it is gone.