Payload to Update AR Invoice DFF in Oracle ERP Cloud

We have REST Service “receivablesInvoiceDFF“to Create an AR Invoice DFF, but unfortunately we cannot update DFF with REST Service. We have a SOAP Service “ERP Object Descriptive Flexfield Update Service” to update DFF. This is a generic service to update DFF of several entities.

Below is the sample payload:

<!-- WSDL https://<hostName>:443/fscmService/ErpObjectDFFUpdateService -->
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:typ="http://xmlns.oracle.com/apps/financials/commonModules/shared/model/erpIntegrationService/types/" xmlns:erp="http://xmlns.oracle.com/apps/financials/commonModules/shared/model/erpIntegrationService/">
   <soapenv:Header/>
   <soapenv:Body>
      <typ:updateDffEntityDetailsAsync>
         <!--Optional:-->
         <typ:operationMode>SINGLE</typ:operationMode>
         <!--Optional:-->
         <typ:object>
            <!--Optional:-->
            <erp:EntityName>Receivables Invoice</erp:EntityName>
            <!--Optional:-->
            <erp:ContextValue>#NULL</erp:ContextValue>
            <!--Trx Number:-->
            <erp:UserKeyA>73003</erp:UserKeyA>
            <!--Customer Trx ID:-->
            <erp:UserKeyD>300000019480136</erp:UserKeyD>
            <!--Optional:-->
            <erp:DFFAttributes>{"ATTRIBUTE1":"99900"}</erp:DFFAttributes>
         </typ:object>
         <!--<typ:callbackURL></typ:callbackURL>-->
      </typ:updateDffEntityDetailsAsync>
   </soapenv:Body>
</soapenv:Envelope>

Below are the details of User Keys

User Key Details Comments
User Key ATransaction Number 
User Key BBatch Source NameNot Mandatory if Transaction Number is Unique.
User Key CSet NameNot Mandatory if Transaction Number is Unique.
User Key DTransaction IdentifierThis is not present in the Billing Transaction workbench and need to create the BIP report to retrieve this. Technical attribute is CustomerTrxId