In this week, i switch from MH lamp to HPS lamp.
from day 38 to now, day 41, the plants seem wilted, I thought it was drought but when I gave them drink nothing changed.
I think you are underwatering. And the pot size is 9l. I think you should give at least 1l of water or more. And before next feeding lift the pot and u can feel the weight so you know if the pot is dry. And maybe move down your lamp. Also make sure air conditioning is good. But this is just my opinion.