How to make top of page in alv to be printed.

hello expert:

i used following function to output alv.

but after been printed into spool, i cannot find the top of page.

how to set the print parameter to print the top of ALV.

CALL FUNCTION 'REUSE_ALV_GRID_DISPLAY'

EXPORTING

i_callback_program = w_repid

i_callback_html_top_of_page = 'HTML_TOP_OF_PAGE'

is_layout = wa_layout

it_fieldcat = it_fieldcat

TABLES

t_outtab = it_comp

EXCEPTIONS

program_error = 1

OTHERS = 2.

thank you and best regards,

Kevin Gao