ERROR- PRICING QUANTITY DOES NOT EQUAL ORDERED QUANTITY at Copy Order

We are facing a weird issue with Pricing UOM on the sales order line

for some reasons the pricing UOM is missing in the sales order line

when we try to copy this order to a new order, we are getting the attached message 'Pricing Quantity does not equal Ordered Quantity"

but when we try to manually add another line to the same so line, the pricing UOM is filled automatically

This is on 11i. What could be the issue

Please advise what am I missing

Darsh