Message type: E = Error
Message class:  OIC_SDP - Billing messages 
Message number: 007
Message text: Only Posting status with 'L' can be rejected
The invoice approval process is activated for the billing type of the
document. Due to this, the billing document with a posting status other
than 'L' cannot be rejected.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
The invoice with this posting status cannot be rejected.
Ask your analyst to correct and approve the invoice.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message OIC_SDP007 indicates that a posting can only be rejected if its status is 'L', which typically stands for "Locked" or "In Process." This error usually occurs in the context of document processing, such as in the SAP S/4HANA or SAP ERP systems, where certain actions can only be performed on documents that are in a specific state.
Cause: The error arises when you attempt to reject a posting that is not in the 'L' (Locked) status. This could happen due to several reasons: The document has already been processed or completed, and its status has changed to something other than 'L'. The document may have been posted or finalized, making it ineligible for rejection. There may be a misunderstanding of the document's current status.
Solution: To resolve this error, you can take the following steps: Check Document Status: Verify the current status of the document you are trying to reject. Ensure that it is
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