Try
call function 'FI_ITEMS_DISPLAY' exporting caller_repid = lv_repid " you report acctype = space " space to bypass some part of logic (but test other sequels) i_u_save = 'A' is_u_variant = is_variant " with your report too x_grid = 'X' tables it_items = lt_items.
But I ask again, whid did you copy standard report when there are options to add fields in it ?
Regards,
Raymond