Message type: E = Error
Message class:  /SAPAPO/PUIA_MESS -  
Message number: 230
Message text: Enter item number for reference document &1
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The SAP error message /SAPAPO/PUIA_MESS230 Enter item number for reference document &1 typically occurs in the context of SAP Advanced Planning and Optimization (APO) when a user is trying to perform an action that requires specifying an item number for a reference document, but the item number has not been provided.
Cause: Missing Item Number: The most common cause of this error is that the user has not entered an item number for the specified reference document (e.g., a sales order, purchase order, or production order). Incorrect Document Type: The reference document type may not support item-level processing, leading to the requirement for an item number being overlooked. User Input Error: The user may have mistakenly skipped the item number field or entered an invalid value.
Solution: Enter Item Number: The immediate solution is to ensure that you enter a valid item number for the reference document specified in the error message. Check the document to
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