Cost scenario api giving error "The value of the attribute CostOrgName isn't valid"

Summary: Cost scenario creation by API is not working "

API POST method URL :https://****/fscmRestApi/resources/11.13.18.05/costScenarios

Payload :

{    "ScenarioNumber": "IECS3", 
  "CostOrgName": "IE ORG",   
"CostBookCode": "IE CostBook",   
"EffectiveStartDate": "2025-05-24"
}

Response :

"

  "title": "Bad Request",    "status": "400",   
"o:errorDetails": [        {            "detail": "The value of the attribute CostOrgName isn't valid.",         
  "o:errorCode": "FND:::FND_CMN_INVALID_ATTRB_API_SERV"

"

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