Can't place Small Soul Core in Stone Altar. Act 3

As the topic says, I'm essentially locked out from progress. In Act 3 Juquani's Mechanarium I can't interact with the Stone Altar. I click it, character heads towards it, but it's not opening any inventory or anything I can interact with. Even tried draggin the damn thing to the altar but that drops the item on the floor (obviously) but just to show I've tried everything...
I've looked around the map numerous times, there's just one altar.


Edit: Few hours later, after numerous tries, loggin off, switching characters and so on and so on. I came back after work and it suddenly worked. Simply clicked the damn stone and my character put the stone in the altar and I could continue. CLEARLY a bug