Message type: E = Error
Message class:  FINS_SIS_CUST - Impl. of Doc. Splitting: Customizing 
Message number: 124
Message text: Project ID is a required field; Enter a valid Project ID
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The SAP error message FINS_SIS_CUST124 indicates that a required field, specifically the Project ID, is missing or invalid in the context of a transaction or process you are trying to execute. This error typically occurs in the SAP system when dealing with project-related data, such as in Project System (PS) or Financials.
Cause: Missing Project ID: The most common cause is that the Project ID field is left blank when it is required for the transaction. Invalid Project ID: The Project ID entered may not exist in the system or may not be valid for the context in which you are working. Authorization Issues: Sometimes, the user may not have the necessary authorizations to view or access the specified Project ID.
Configuration Issues: There may be configuration settings in the SAP system that require a Project ID for certain transactions, and these settings may not be properly aligned with the data being processed.
Solution: Enter a Valid
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