Message type: E = Error
Message class:  FICUSTOM - Customizable Messages for Funds Management 
Message number: 303
Message text: Document &1/&2 belongs to a document chain. (AWREF/AWTYP) &3/&4
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The SAP error message FICUSTOM303 indicates that a document you are trying to process is part of a document chain. This typically occurs in the context of financial documents, where certain documents are linked together in a chain (for example, an invoice and its associated payment).
Cause: The error arises when you attempt to perform an action on a document that is part of a chain, but the action is not allowed due to the document's status or its relationship with other documents in the chain. The specific parameters in the error message (AWREF/AWTYP) refer to the reference and type of the document that is causing the issue.
Solution: To resolve this error, you can take the following steps: Check Document Status: Verify the status of the document you are trying to process. If it is part of a chain, ensure that all related documents are in a status that allows the action you are
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