Message type: E = Error
Message class:  CNV_CDMC_CA - CDMC Clearing Analysis 
Message number: 020
Message text: SAP Note already exists in the list
You have attempted to add an SAP Note to the list that is already
available in the list.
It is not possible to add same SAP Note to the list twice.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message CNV_CDMC_CA020 indicates that there is an attempt to add a note to a list where that note already exists. This typically occurs in the context of the SAP Conversion and Data Migration Cockpit (CDMC) when managing notes or entries related to data migration projects.
Cause: The error is caused by trying to add a note or entry that is already present in the list. This can happen due to: Duplicate entries being processed. An attempt to re-add a note that has already been included in the migration project. A programming or configuration error that leads to the same note being referenced multiple times.
Solution: To resolve this error, you can take the following steps: Check the List of Notes: Review the list of notes or entries in the migration project to confirm that the note in question is indeed already present. Remove Duplicate Entries: If you find that the note is duplicated, remove the duplicate entry from
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