How to re-use Serial numbers received through RMA

Business has a scenario where the goods are shipped out to customer. The parts are serial controlled. Sometimes, the goods are returned through RMA with those serial numbers into warehouse.

If business try to re-use the serial numbers which are received via RMA, they were not able to use again. Currently, as a work around, they place "." as suffix after the serial number (received via RMA) and ship the goods. However, this practice has led to other issues during pack and in warranty administration.

How a serial number which is received via RMA can be re-use again?

Currently, the serial uniqueness is set to "Unique within Model and Inventory Items" and Generation is set to "User defined" at Inventory organization parameters.