do your business use production orders?
this abnormal balance of COGS appears to my PnL whereas it comes from production order :
from PnL (negative balance) :
It comes from production order (I trace it from inventory tab that item of inventory has opening balance and purchase are 0 / zero but closing balance filled from production order so then using formula opening balance + purchase - closing balance makes negative balance) :
Do you see this @lubos ? I think this is wrong.