3773294 - Custom field populated via FIN_ACDOC_SUBSTITUTION BAdI is empty in Manage Customer Line Items app

A custom field (for example, Project Number) has been created and populated using the Substitute Accounting Document Item (FIN_ACDOC_SUBSTITUTION) BAdI. The field value is correctly stored in the underlying CDS views and is available in the Settings dialog of the Manage Customer Line Items app. However, the custom field remains empty. 

SAP S/4HANA Cloud Public Edition

The custom logic is executed only when a new customer line item is created or an existing customer line item is changed. Therefore, customer line items that existed before the implementation of the custom logic do not trigger the substitution, and the custom field remains empty.

As a workaround, perform a "dummy change" on the affected customer line items using the Edit Line Items function in the Manage Customer Line Items app. Updating a changeable field and saving the changes triggers the logic, allowing the custom field to be populated. 

Custom fields for the "Manage Customer Line Items"... - SAP Community

custom field, manage customer line items, journal entry substitution, FIN_ACDOC_SUBSTITUTION, badi, blank, empty , KBA , FI-FIO-AR-IS-2CL , Reporting Apps: Public Cloud , How To