Hi,
Change to loop assigning field symbol should be better:
field-symbols <WA_INT> type [whatever your type is].
Loop at Int_Tab ASSIGNING <WA_INT>.
WA_std_tab-ZZMATERIAL = WA_INT-ZZMATERIAL.
WA_std_tab-ZZGL_ACCOUNT = WA_INT-ZZGL_ACCOUNT.
WA_std_tab-ZZAMOUNT = WA_INT-ZZAMOUNT.
WA_std_tab-ZZCUSTOMER = WA_INT-ZZCUSTOMER.
ENDLOOP.
Regards,
Custodio