https://userapps.support.sap.com/sap/support/knowledge/en/1986264
1986264 - ARA: Rule set changes for FBZ0 object F_REGU_BUK | SAP Knowledge Base Article
Within SAP standard rule set, in functions AP01 , and AR01 , there is a rule for t-code FBZ0 where the ACTVT 12 and 13 are enabled for auth object F_REGU_BUK...