Message type: E = Error
Message class:  ICC_FI_CN - Für die Meldungen extern vornum. Belege 
Message number: 023
Message text: Number of last document issued is not in book (documents &1 to &2)
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The SAP error message ICC_FI_CN023, which states "Number of last document issued is not in book (documents &1 to &2)," typically occurs in the context of financial accounting and document management within SAP. This error indicates that there is a discrepancy in the document numbering sequence for financial documents, which can lead to issues in reporting and data integrity.
Cause: Document Numbering Gaps: The error usually arises when there are gaps in the document numbering sequence. This can happen if documents were deleted, or if there was an interruption in the document creation process. Incorrect Configuration: The configuration settings for document number ranges may not be set up correctly, leading to inconsistencies. Data Migration Issues: If data was migrated from another system, there may be inconsistencies in the document numbers. Parallel Processing: If multiple users or processes are trying to create documents simultaneously, it may lead to conflicts in document numbering.
Solution: Check Document Number Ranges: Verify
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