Message type: E = Error
Message class:  FAGL_POSTING - Messages for FAGL_POSTING EhP3 Relating to New Functions 
Message number: 009
Message text: Enter a sorting indicator
For an account managed on an open item basis for specific ledger groups,
an entry is stored in an index table for each line item. In this way,
line item display is possible for the general ledger view and the entry
view.
Here you can create a sort key indicator for an account. In this way,
the items are sorted in the display by the sort sequence.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Enter a sort key indicator.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message FAGL_POSTING009, which states "Enter a sorting indicator," typically occurs during the posting process in the General Ledger (G/L) accounting module. This error indicates that a sorting indicator is required for the transaction you are trying to execute, but it has not been provided.
Cause: Missing Sorting Indicator: The sorting indicator is a required field in certain G/L postings, especially when dealing with specific document types or when certain configurations are in place.
Configuration Issues: The system may be configured to require a sorting indicator for certain types of postings, and if this is not set up correctly, it can lead to this error. Transaction Type: The type of transaction you are trying to post may inherently require a sorting indicator based on the business rules defined in your SAP system.
Solution: Enter a Sorting Indicator: When you encounter this error, check the posting screen for a field labeled "Sorting Indicator" or similar.
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