Item cost Adjustment

We received a refund for $10,000 from one of our vendors and applied to GL 54900 for merchandise and keep the good in our inventory, due to the fact that the merchandise is not selling that great. At this point we paid the original invoice in full and we don’t have any other invoices pending for payment.
if the refund was applied to merchandise and reduce the cost of goods . Can I do a fixt cost to the item as well.
We have 1,155 units available in inventory, the original cost was $8.00.