https://userapps.support.sap.com/sap/support/knowledge/en/3028011
3028011 - Replacement of credit master data fields (table KNKK, fields REVDB, DTREV, SBGRP, DBEKR)...
SAP Credit Management (FSCM) has been activated and replacements are required for fields KNKK-REVDB, KNKK-DTREV, KNKK-SBGRP, KNKK-DBEKR.