is the medium wet? Could be waterlogged to the point where it can't uptake nitrogen. Also what are your temperatures and PH.
the medium was wet which i noticed i didn't have any drainholes so i promptly fixed that. lol too baked to notice what can you do. lol and the temp is cool aroun 60 to 73 i'd say. don't know the ph but i'm pretty sure it was waterlogged.