#!usr/bin/perl
use DBI;
use Spreadsheet::ParseExcel;
use Spreadsheet::ParseExcel::SaveParser;

$month=$ARGV[0];
$month or $month=`date --date='1 day ago' +%B`;
chomp $month;
print "Month:$month\n";

my $dbh = DBI->connect("DBI:mysql:database=MIS_Reports;host=172.16.15.
+104;mysql_socket=/opt/lampstack-5.5.27-0/mysql/tmp/mysql.sock","root"
+,"",      {'RaiseError' => 1});

#---------------------------------------------------------------------
+------------------------------------#


# Open an existing file with SaveParser
my $parser   = Spreadsheet::ParseExcel::SaveParser->new();
my $template = $parser->Parse('B_MUM_dashboard_month_latency_corrected
+_FDB.XLS');

@tables=("MIS_Overall","MIS_P2P","MIS_P2A","MIS_A2P");
$sheet_no=0;



foreach $table (@tables)
{
    chomp $table;

    my $sth = $dbh->prepare("SELECT * from $table where monthname(Date
+)='$month'" );
    $sth->execute() or die $DBI::errstr;

    # Get the first worksheet.
    my $sheet = $template->worksheet($sheet_no);
    my $row  = 2;
    my $col  = 1;

    while (my @row = $sth->fetchrow_array())
    {
        $col=1;
            foreach my $value (@row)
            {
            $sheet->AddCell( $row, $col, $value );
            ++$col;
        }
        $row++;
    }
    $sheet_no++;
}
$template->SaveAs('B_MUM_dashboard_month_latency_corrected_FDB_12-08-2
+015.XLS');
[download]

Error: Can't call method "worksheet" on an undefined value at parse_excel_multisheet.pl line 33

This means that $template was not initialized properly. Check the return value of

my $template = $parser->Parse('B_MUM_dashboard_month_latency_corrected
+_FDB.XLS');
[download]

like this

my $filename = 'B_MUM_dashboard_month_latency_corrected_FDB.XLS';
my $template = $parser->Parse($filename)
    or die "Couldn't read '$filename': " . $parser->error;
[download]

That way, you find out why your template was not initialized properly.