1808919 - Extension Field not Populated in Extension Scenario "Sales Order - Item to Purchase Request - Item"

You added in the Adaptation Mode an extension field to the Sales Order on Item level. And in Further Usage of Extension Field, you then activated the extension scenario "Sales Order - Item to Purchase Request - Item".
The details for the Extension Scenario are:

• "Sales Order - Item" to "Customer Demand - Order Line Item"
• "Customer Demand - Order Line Item" to "Purchase Request Planning Details - Item"
• "Purchase Request Planning Details" - Item to "Purchase Request - Item"

However, when you create a new Sales Order, the field value is correctly passed on to the Customer Demand, but it does not propagate to the Purchase Request Planning Details nor to the Purchase Request.

 SAP Business ByDesign

At present, the propagation of extension fields is not supported for Planning documents. The Business Objects in the Planning Area are dynamic, therefore, it is not possible to definitely match the Demand with the Supply.
So, even if the Sales Order Material Flow shows the Purchase Request with Pegged Quantity, this cannot be propagated. The pegging relation is dynamic and can be changed if the MRP is re-run.

Note that in the case of Third-party Order Processing, the propagation of the extension field value from the Third-Party Sales Order to the Purchase Request is working as this does not involve Planning.

The system is working as designed behavior.

Extension Field, Sales Order - Item to Purchase Request - Item , KBA , AP-PRP , Purchase Request Processing , How To