Dear Experts,
We are trying to post a cancellation to a purchase invoice.
When we post /PurchaseInvocie(id)/Cancel we receive the following response
{ "error": { "code": -5006, "message": { "lang": "en-us", "value": "The requested action is not supported for this object." } } }
According to the service layer API documentation (SAP 9.3 PL3) this function should be supported -

The steps we are doing -
1. Post /PurchaseDeliveryNotes
{ "CardCode": "VO_Main", "DocDate": "2018-06-20", "DocDueDate": "2018-07-20", "DocumentLines": [ { "ItemCode": "SP234325", "Quantity": "100", "UnitPrice": "30" } ] }
Response - 201 Created
{ "odata.metadata": "https://.....:50000/b1s/v1/$metadata#PurchaseDeliveryNotes/@Element", "DocEntry": 460, "DocNum": 436,
2. Post /PurchaseInvoices
{ "CardCode": "VO_Main", "DocDate": "2018-06-25", "DocDueDate": "2018-07-25", "DocumentLines": [ { "BaseType": 20, "BaseEntry": 460, "BaseLine": 0 } ] }
Response - 201 Created
{ "odata.metadata": "https://......:50000/b1s/v1/$metadata#PurchaseInvoices/@Element", "DocEntry": 457, "DocNum": 424, "DocType": "dDocument_Items", "HandWritten": "tNO",
3. Post /b1s/v1/PurchaseInvoices(457)/Cancel
Response - 400 Bad Request
{ "error": { "code": -5006, "message": { "lang": "en-us", "value": "The requested action is not supported for this object." } } }