Please verify that your output inventory movement complies with the following considerations:

1. Confirm that the Inventory Movement is [Activated]
2. Confirm that your User Profile has the Security Authorisations to [Assign] this type of Inventory Movement
3. For Serial or Lot Number controlled Items: Verify there is a Serial Number on the corresponding entry record
4. Confirm that the Inventory movement has at least one active entry

If after confirming the above considerations it is still not possible to [Assign] the Inventory Movement, please open a Support Ticket.