Unable to Mass Cancel PO Lines using REST API and SOAP API in Oracle Fusion

Summary:

Hello,

We are trying to mass cancel multiple PO lines in Oracle Fusion Procurement.
We have attempted the following approaches:

1. REST API – Used PATCH on draftPurchaseOrders resource with CancelFlag=true for multiple lines.
2. SOAP API – Used cancelPurchaseOrder operation with multiple <CancelOrderLine> elements in the payload.

However, both methods are not working as expected. The change order is either not created or only one line gets canceled.

Can you help if there is any other way to mass cancel PO Lines? If at all there is a possibility to do this using FBDI can you, please share sample template?

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