When we buy a product, we buy by carton and number of units will be 10, but when some of the units are damaged I need to issue credit request, then when I raise a new Purchase Invoice, enter the quantity as a negative, system tend to take whole carton, how can I do the returns only for the damaged units? For example came 10 cartons, (10x10 = 100Units), one carton damaged, opened and check, only 4 pks are damaged and need to request for credit for 4 packs and remove it from inventory. But when I put -4, the stock it picks as -40. How to do this please. Thanks

