Message type: E = Error
Message class:  FAGL_MIG - Migration to New General Ledger Accounting 
Message number: 054
Message text: Migration plan / company code / ledger combination not found
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The SAP error message FAGL_MIG054 indicates that a migration plan, company code, and ledger combination cannot be found during the migration process, typically when transitioning from classic General Ledger (G/L) accounting to the new G/L accounting in SAP. This error can occur during the migration of financial data, particularly when using the Migration Tool for New G/L.
Cause: Missing Migration Plan: The migration plan for the specified company code and ledger has not been created or is not active. Incorrect Configuration: The configuration settings for the migration plan may not be correctly set up in the system. Company Code or Ledger Issues: The specified company code or ledger may not exist or may not be properly defined in the system. Authorization Issues: The user may not have the necessary authorizations to access the migration plan or related data.
Solution: Check Migration Plan: Go to the transaction code OBY6 (or the relevant configuration path) to check if the migration
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