Message type: E = Error
Message class:  CNV_IUUC_REPL_ADV_SE - MEssage class for package CNV_IUUC_REPL_ADV_SETTINGS 
Message number: 023
Message text: Position & is already available in modification overview
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The SAP error message CNV_IUUC_REPL_ADV_SE023 typically occurs during the data migration or replication process, particularly when using the SAP Landscape Transformation (SLT) Replication Server or during the use of the SAP S/4HANA Migration Cockpit. This error indicates that a specific position (or entry) is already present in the modification overview, which can lead to conflicts or duplication issues.
Cause: Duplicate Entries: The error usually arises when there are attempts to replicate or modify data that already exists in the modification overview. This can happen if the same data is being processed multiple times or if there are overlapping replication tasks. Inconsistent Data State: If the data state in the source system is inconsistent or if there are issues with the data extraction process, it can lead to this error.
Configuration Issues: Incorrect configuration settings in the SLT or migration cockpit can also lead to this error.
Solution: Check Modification Overview: Review the modification overview to identify
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