Message type: E = Error
Message class:  FKK_ID_XX_ODN - ODN message 
Message number: 004
Message text: Number range assignment is not valid for the document class &1
The system has derived the document class from the Customizing, however
it was not able to retrieve the number range assignment for this
document class. The reason is that the assigned number range is not
valid anymore.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Make the necessary assignment in configuration step <LS>Assign Number
Ranges to Company Codes and Document Classes</>.
Maintain the Customizing activity
<DS:SIMG._FICAOD_ODNNR_DET>Assign Number Range to Document Classes</>.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message FKK_ID_XX_ODN004 indicates that there is an issue with the number range assignment for a specific document class in the context of contract accounts receivable and payable (FI-CA). This error typically arises when the system attempts to create or process a document, but the number range assigned to that document class is either not defined, not valid, or not properly configured.
Cause: Number Range Not Defined: The number range for the specified document class has not been defined in the system. Number Range Not Assigned: The document class may not have a valid number range assigned to it. Number Range Interval Issues: The number range intervals may be closed or exhausted, meaning there are no available numbers left to assign. Configuration Errors: There may be configuration errors in the number range settings or in the document class settings.
Solution: To resolve the error, you can follow these steps: Check Number Range Configuration: Go to the transaction
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