u/Same-Till-7882

I'm stuck at this part. I've already pulled every lever I could find and opened all the doors that were closed, but I just can't progress. I have a lever in my inventory, but I can't place it in the slot where it seems to belong. I've already left the area, restarted the game, and revisited other locations to reload everything, but nothing worked. Does anyone know what I'm supposed to do here?