3657677 - Error "You can only create service confirmation items with preceding items" when creating service confirmation using API

When trying to create service confirmation, using the API Service Confirmation A2X (API_SERVICE_CONFIRMATION_SRV), the error: "You can only create service confirmation items with preceding items.". The service order referenced on the payload is correctly created and released for confirmation, even though, the error is thrown.

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SAP S/4HANA Cloud Public Edition

POST <host>/sap/opu/odata/sap/API_SERVICE_CONFIRMATION_SRV/A_ServiceConfirmation HTTP/1.1
Content-Type: application/json

{ 
"ServiceConfirmationType": "SVC1", 
"ServiceConfirmationDescription": "Test"
"ReferenceServiceOrder" : "8000001111",
"SoldToParty" : "171000001",
"to_Item" : [
  {
    "ReferenceServiceOrderItem" : "20",
    "ActualServiceDuration" : "2.000",
    "ActualServiceDurationUnit" : "H",
    "Quantity" : "1",
    "QuantityUnit" : "HR",
    "ExecutingServiceEmployee": "9988776656"
  }
 ]
} 

This error is thrown because there's no reference to the service order on the item level of the payload.

Add the field  "ReferenceServiceOrder" on the item node as well. Check bellow the corrected version of the payload used as example before:

{ 
"ServiceConfirmationType": "SVC1", 
"ServiceConfirmationDescription": "Test"
"ReferenceServiceOrder" : "8000001111",
"SoldToParty" : "171000001",
"to_Item" : [
  {
    "ReferenceServiceOrder" : "8000001111",
    "ReferenceServiceOrderItem" : "20",
    "ActualServiceDuration" : "2.000",
    "ActualServiceDurationUnit" : "H",
    "Quantity" : "1",
    "QuantityUnit" : "HR",
    "ExecutingServiceEmployee": "9988776656"
  }
 ]
} 

Service Confirmation (A2X) | SAP Help Portal

Create Service Confirmation | SAP Help Portal

service confirmation, service order, API_SERVICE_CONFIRMATION_SRV, OData V2, A_ServiceConfirmation, A_ServiceConfirmationItem, CRM_ORDERADM_I/032 , KBA , CRM-S4-SRV-SCO-2CL , S4CRM: Service Confirmation (Public Cloud) , Problem