while (my $row = $csv->getline($FILE1)) 
{
                        # $row is a reference to a row
    my @fields = @$row; # this explicitly de-references
    my $id1 = $fields[1];

    
    if (exists $file2{$id1})
    {
        $csv->print ($FILE3, "HL", @fields); #both files
    }
    else
    {
        $csv->print ($FILE3,"NOT_HK", @fields);  #file1 only
    }
}