Message type: E = Error
Message class:  FINS_FI_MIG - SAP S/4HANA Finance: Data Migration 
Message number: 721
Message text: Migration activity &1 still running
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The SAP error message FINS_FI_MIG721 indicates that a migration activity is still running in the system. This typically occurs during the migration process of financial data, especially when using the SAP S/4HANA Migration Cockpit or similar tools.
Cause: Ongoing Migration Process: The most common cause of this error is that a previous migration activity has not yet completed. This could be due to long-running processes, system performance issues, or a previous migration task that has not been properly terminated. Locking Issues: Sometimes, database locks or other processes may prevent the migration from completing. System Errors: Unexpected system errors or crashes during the migration process can also lead to this message.
Solution: Check Migration Status: Go to the Migration Cockpit or the relevant transaction code (like FINS_MIGRATION) to check the status of the migration activities. Ensure that no other migration tasks are currently running. Wait for Completion: If you find that a migration task is still running, you
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