Message type: E = Error
Message class:  FICUSTOM - Customizable Messages for Funds Management 
Message number: 288
Message text: The internal order is already used in a different document
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The SAP error message FICUSTOM288 indicates that an internal order you are trying to use is already associated with another document. This typically occurs in financial transactions where internal orders are used to track costs and revenues.
Cause: Duplicate Usage: The internal order has already been assigned to another financial document (e.g., invoice, journal entry, etc.), and SAP does not allow the same internal order to be used in multiple documents simultaneously. Incorrect Document Type: The document type you are trying to create may not allow the use of the specified internal order. Order Status: The internal order may be in a status that does not permit further postings (e.g., closed or completed).
Configuration Issues: There may be configuration settings in the system that restrict the use of internal orders in certain scenarios.
Solution: Check Internal Order Usage: Verify if the internal order is already assigned to another document. You can do this by checking the internal
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