Message type: E = Error
Message class:  FKK_ID_XX_ODN - ODN message 
Message number: 057
Message text: Number range already assigned to a different document class
You have tried to assign a number range that  has already been assigned
to a document class with different digital signature customizing. This
may cause gaps in the reporting.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Assign a different number range to the document class.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message FKK_ID_XX_ODN057 indicates that there is an issue with number range assignment in the context of the SAP Contract Accounts Receivable and Payable (FI-CA) module. Specifically, this error occurs when you attempt to assign a number range that has already been assigned to a different document class.
Cause: Number Range Conflict: The number range you are trying to use is already assigned to another document class. In SAP, each document class can have its own number range, and if a number range is already in use by a different document class, you will encounter this error.
Configuration Issues: There may be a misconfiguration in the number range settings for the document classes in the system. Custom Development: If there are custom developments or enhancements in the system, they might be trying to use a number range that is not properly configured.
Solution: Check Number Range Configuration: Go to the transaction code SNRO (Number Range
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