I can change it in VA02 main line item's(10) structure tab which is shown in image. But I can't change these subitems using bapi_salesorder_change.
If I pass HG_LV_ITEM as 10 and itm_number as 16 which is item no. of that perticular component, in bapi item table, component quantity is not changing.
Do anyone know how to change that field using BAPI?