Message type: E = Error
Message class:  FIRU_IMPRTCSTMSDECLN - Message class for Import Customs Declaration 
Message number: 704
Message text: Inbound Delivery &1 already used in Import Customs Declaration &2
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The SAP error message FIRU_IMPRTCSTMSDECLN704 indicates that an inbound delivery (identified by &1) has already been used in an import customs declaration (identified by &2). This error typically arises in the context of logistics and customs processing within SAP, particularly when dealing with inbound deliveries and customs declarations.
Cause: The error occurs because the system is designed to prevent the same inbound delivery from being used in multiple customs declarations. This is a safeguard to ensure that each delivery is accounted for only once in the customs process. If you attempt to reference an inbound delivery that has already been linked to a customs declaration, the system will generate this error.
Solution: To resolve this error, you can take the following steps: Check the Inbound Delivery Status: Verify the status of the inbound delivery in question. You can do this by navigating to the inbound delivery document in SAP and checking if it is already
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