Unwanted CGI execution on Refreshing

[romy_mathew]

I am trying to create a e commerce website but my current problem is when I add a product to my bag --> goes to bag.html where it shows the products I have selected but when I refresh the page the same items get incremented every time i refresh

I tried x.pl for selecting the page --> moves to chart.pl--> moves to mybag.html

But its fails every time i refresh my bag page the last item i added get incremented Please find the code for chart.pl below

#!/usr/bin/perl -w
#chart.pl
use strict;
use CGI qw(:standard);
use CGI::Carp qw(fatalsToBrowser);
use CGI::Session;
use Apache::Session::MySQL;
use DBI;
use Template;
use 5.010;
use rightplacedb;
use webdb;
use Data::Dumper;

$| =1;
print "content-type: text/html\n\n";


my $dbh = webdb::connect() or die "Cannot connect to database $@\n";
my $cookie;
my %session;
my $template;

my $sess_id = cookie('CUSTOMER_ID');

print "session id : $sess_id<br>";
        
tie %session, "Apache::Session::MySQL",$sess_id,
    {
        Handle    => $dbh,
        LockHandle    => $dbh
    };


my $page = param('t_shirt');
my $id   = param('id');
my $price = param('price');

given ($page) {

        when ($page eq 'add_to_chart') 
        {
            
            if (exists $session{$id}) {
                # update the quanity of the items
                $session{'$id'}{'price'} = $price;
            }
            else 
            {
                $session{$id} = $id;
                $session{'$id'}{'price'} = $price;
            }
    print "<br>check the price $session{'$id'}{'price'}";

    print "<br>the : $session{'item_code'}";

    my $array = $session{'item_code'};
    
    my @selected_item = @$array;

    push(@selected_item,$id);

    print "<br>before database : @selected_item<br>";

    $session{'item_code'} = \@selected_item;
    print "<br>the : $session{'item_code'}";

    my $bag_id = $session{'item_code'};
    

    print "<br>my bag contains : @$bag_id<br>";
    
    
    $template = '/home/romy/public_html/rightplace/template/src/mybag.
+html';


        

    $dbh->disconnect();

    }
    
    default {
            $template = '/home/romy/public_html/rightplace/template/sr
+c/entry.html';

        }
}
        
untie(%session);



my $vars = {
        position    => $id,
        Brands     => $price,
    };


my $tt = Template->new ({
            INCLUDE_PATH => [
                    '/home/romy/public_html/rightplace/template/src/',
                    '/home/romy/public_html/rightplace/template/lib/',
                    ],
            WRAPPER        => 'wrapper',
            ABSOLUTE    => 1,
            RELATIVE    => 1,
    });



$tt->process($template,$vars)|| die "Failed to execute the template $t
+t->error() \n";