I am trying to enable the Account Assignment Group in Sales Order and I understand that there is a SNOTE but it requires a higher version of SAP APPL than we currently have. So my alternative route is to create a User Exit entry suggested here https://answers.sap.com/questions/910561/index.html , However there seems to be more to it for the Account Assignment Group (VBAP-KTGRM) , I can enable the field without an issue. But as soon as you change it and press confirm/enter or go onto the next part, it instantly reverts back to the original value.
I assumed the value would have to be updated in USEREXIT_MOVE_FIELD_TO_VBAP , however i've debugged for hours and nothing seems to trigger this. So I'm hoping there is just something simple I am missing. Ideas?
Simple solution would be to not go for the complicated logic of using user exit.
When you create a billing document from the sales order the same account assignment group gets carried forward and in billing this field is editable and can be changed.