Delirium No Progression

I've been trying to finish my Grand Mirror fog area, but every time I do a delirious map, I would finish the map with x%, let's say 70% and typically, it should carry over to the next map but it restarts at a random number. I thought it was a specific fog location that was bugged so I started a new Grand Mirror location and the same bug keeps happening.

Sometimes, in a map, I dont gain any progression even after killing all the rare mobs. Tested with and without a delirium tablet.

I am not able to finish the fog and reach the Simalacrum. PLEASE FIX

Would like to confirm I'm also having this bug - started this part of the questline earlier today, got to mid-30s, had to go out. Came back this evening and each time I switch map it resets back to 17%

EDIT: Put in a Delirium tablet while within that first Grand Mirror area, south of the tree. Weirdly set my Deliriousness to 25%, but no Rare, Unique etc. kill would shift it.