Can not issue customer RMA item into a new MNT WO execution

Summary:

Hi Team,

I was not able to issue a customer RMA item into a new MNT WO.

Content (required):

We have a requirement where we need to upgrade the customer's defective part to a new/upgraded part.

For this we proposed below solution :

RMA customer defective part X

Upgraded part Y is already in the inventory and asset is created for this

Create MNT WO for upgraded part Y

issue part X

Ship Part Y to customer

But while issuing the part X to Part Y in the review dispatch list, I am not getting the Serial/Asset in the LOV. Subinventory selection is correct.