Message type: E = Error
Message class:  FINS_FI_MIG - SAP S/4HANA Finance: Data Migration 
Message number: 150
Message text: Data migration is not yet finished: Updating of documents is not possible
Either there is a due data migration not yet started or the status of
data migration to the SAP S/4HANA Finance has not yet been set to
"completed" which is an explicit and manual step in the IMG for data
migration.
Since data migration is still running or even not yet started, posting
or changing of documents is not allowed.
The system displays an error message (as standard message type).
If the migration is due but not yet started, start it in the IMG.
Otherwise wait until the data migration has been finished. Then you can
set the migration to "completed" in the IMG for data migration.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message FINS_FI_MIG150 indicates that the data migration process is not yet complete, which prevents the updating of financial documents. This error typically occurs during the migration of financial data to the new system or during a system upgrade where financial data is being transferred or transformed.
Cause: Incomplete Migration Process: The migration process for financial data has not been fully completed. This could be due to various reasons such as: Migration jobs are still running. Errors occurred during the migration that halted the process. The migration was not properly initiated or configured. Locking Mechanism: The system may have a locking mechanism in place that prevents updates to financial documents until the migration is fully completed.
Configuration Issues: There may be configuration settings that are preventing the completion of the migration process.
Solution: Check Migration Status: Verify the status of the migration process. You can do this by checking the relevant transaction codes (like SLG1 for application
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