Message type: E = Error
Message class:  CNV_CDOP_CA - CDOP Clearing Analysis 
Message number: 089
Message text: Activity & is already completed
You want to reexecute an activity that is already completed.
Re-execution of activities of this type is only possible if an  error
occured during the last execution.
It is not possible to re-execute successfully executed activities.
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_CDOP_CA089 typically indicates that a specific activity in the Conversion Process (often related to data migration or system conversion) has already been completed. This message is part of the SAP Conversion Tools and is often encountered during the execution of data migration projects, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
Cause: The error occurs when: You attempt to execute an activity that has already been marked as completed in the system. There may be an attempt to re-run a migration step that is designed to be executed only once. The system may have been incorrectly configured, or there may be a misunderstanding of the migration process flow.
Solution: To resolve this issue, consider the following steps: Check Activity Status: Go to the relevant transaction or tool where the migration activities are being monitored (e.g., SAP S/4HANA Migration Cockpit). Verify the status of the activity in question. If it is marked as
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