Message type: E = Error
Message class:  CNV_PE_MC - Messages for Migration Cockpit context 
Message number: 013
Message text: Migration scheduling failed. Data already migrated.
Migration scheduling failed.
The selected data has been already successfully migrated.
Error
Re-migration of already migrated data is not allowed.
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_PE_MC013 indicates that a migration scheduling process has failed because the data has already been migrated. This typically occurs in the context of SAP S/4HANA migrations or data migrations using the SAP Landscape Transformation (SLT) or other migration tools.
Cause: Data Already Migrated: The primary cause of this error is that the system has detected that the data you are trying to migrate has already been processed in a previous migration run. This can happen if: The migration process was executed more than once for the same data set. There was an incomplete or interrupted migration that left the data in a migrated state. The migration scheduling was attempted without resetting the migration status.
Solution: To resolve the CNV_PE_MC013 error, you can follow these steps: Check Migration Status: Review the migration logs and status to confirm which data has already been migrated. This can usually be done through transaction codes related to the migration tool
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