Record is not rejected by reject record .

Hi Experts.
I was trying to reject the record if customer number is not AARONFIT0001,but the scrolling window still populates with all customer number.

Can someone point out what i have done wrong?

Startup script

l_result = Trigger_RegisterFocus(window Customer_Lookup_Scroll of form Customer_Lookup,  TRIGGER_FOCUS_FILL, TRIGGER_AFTER_ORIGINAL, script FILTER_Data_set);
if l_result <> SY_NOERR then
warning "Focus trigger registration failed.";
end if;

Trigger processing Procedure

{FILTER_Data_set}

if 'Customer Number' of table RM_Customer_MSTR <> "AARONFIT0001" then
reject record;
end if;