Correct process on correcting UOM intraclass conversion and correcting difference after the change

Summary:

We have identified that there's one item that has wrong conversion ongoing on(1carton = 6 each) that we have corrected into(1carton =10 each). however, it seems that after the change, the inventory valuation still calculates it at 6 each instead of the new carton calculation causing an imbalance with the current stock on hand in item quantities(UI) and in the inventory valuation report. What's the correct way to process it? initially, we process all pending transactions and issued out stocks before converting the UOM. Did we do anything wrong in the process?

Change in UOM happens in April, these transactions are all before the UOM conversion though.