How to reverse an ended output order?

A transfer order has been created with a transfer quantity of 42 however only 40 have been actually shipped creating 2 units as ship remain and receive . Transfer status for this remained as created.

I am unable to ship the 2 ship now quantity/receive now quantity since under Posting button, Ship transfer order is grey out.

On the other hand, when I try to cancel the delivery remainder of 2, I get this error:

“The quantity cannot be reduced. The number of inventory transactions on order is too low because the quantity or part of it is referenced by an output order or a production order or is marked against other transactions.”.

Output order pertaining to this transfer order has quantity of 42 and it’s status is “Ended” so I can’t edit the quantity and supposedly end the inventory.

Any suggestions on how I can fix this issue?

Thanks