Solution : https://service.sap.com/sap/support/notes/601757 (SAP Service marketplace login required)
Key words : 
component crm-md-pro-set, crm-md-pro-set, correction report runs automatically, correction report corrects entries, unique index duplicate entriesshadow_import_inc, 'duplicate key' errors occur, start z_repair_comc_attribute report immediately, log'timestamp' file includes, duplicate key reason, attached correction report
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