Message type: E = Error
Message class:  SIAO_DEL - SIAO: Digital Signature Angola 
Message number: 118
Message text: Delivery date &1 Conflict with date maintained in the number range &2
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The SAP error message SIAO_DEL118 indicates that there is a conflict between the delivery date specified in a document and the date maintained in the number range configuration. This typically occurs when the delivery date falls outside the allowed range defined for the number range used for the document.
Cause: Date Conflict: The delivery date you are trying to enter is either earlier than the start date or later than the end date defined in the number range settings. Number Range Configuration: The number range for the document type may have specific date restrictions that are not being met by the delivery date you are trying to use. System Settings: The system may have been configured to restrict certain delivery dates based on business rules or operational requirements.
Solution: Check Number Range Configuration: Go to the transaction code SNRO (Number Range Objects). Find the relevant number range object associated with the document type you are working with. Check the
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