2959195 - Unable to find user for assignment in Manage Credit Memo Request Workflow

• User is not found when changing the current assignment in the Manage Credit Memo Request Workflow Fiori application.
  
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• Error No service found for namespace '', name 'C_SALESDOCUMENTWORKFLOWVH_CDS', version '0001' occurred (transaction /N/IWFND/ERROR_LOG)

• SAP Business Workflow
• SAP S/4HANA 1909
• ABAP PLATFORM 1909 - Application Server ABAP (SAP_BASIS 7.54)
• Manage Credit Memo Request Workflow Fiori application

WF_GDPR, SWF_WORKFLOW, use can't, user not found, T100 Error ID /IWFND/MED170, Request Kind Server OData v2, Package /IWFND/MED_PER_DEV_LANGU, Program /IWFND/CL_MED_SRG_DB_ACCESS===CP, Include /IWFND/CL_MED_SRG_DB_ACCESS===CM00R, Request URI /sap/opu/odata/sap/C_SALESDOCUMENTWORKFLOWVH_CDS/***Hide_due_to_secure_log_level***, manage workflow , KBA , SD-SLS , Sales , BC-BMT-WFM , Business Workflow , OPU-BSE-WFM , Gateway Business Workflow Enablement , Problem