Account Assignment: Order not populated during Returns Delivery

Hello,

The account assignment field : Order number is populated successfully in Delivery Document.

Double clicking the line item in the document > Financial Processing Tab>

But, the same is not populating automatically in Returns Delivery.

Double clicking the line item in the document > Financial Processing Tab>

All the preceding documents have Order number populated successfully, except returns delivery. Can someone please help here why the account assignment field Order is not populated in returns delivery document. Because of which we are not able to do Post Goods Receipt and getting error KI 235 "Account requires assignment to CO object".