Swiftmailer - 两次发送邮件，没有任何内容

I uses the swiftmailer for sending a mail.

My code is:

require_once APPPATH.'libraries/swift_mailer/swift_required.php';
$transport = Swift_SmtpTransport::newInstance('mail.---.com', 25)
                              ->setUsername('----')
                              ->setPassword('---');
$mailer = Swift_Mailer::newInstance($transport);
/* database queries  */
$get_count = $this->db->query("SELECT client_id, email FROM `tbl_client`")->result();
foreach($get_count as $count) {
    $id = $count->client_id;
    $c_email = $count->email;
    $today_leads = $this->db->query("SELECT COUNT(*) leads_count FROM `tbl_leads` WHERE DATE(leads_update_on) = curdate() AND client_id = $id")->row();
    $today_leads = $today_leads->leads_count;
    $till_date = $this->db->query("SELECT COUNT(*) leads_till_date FROM `tbl_leads` WHERE client_id = $id")->row_array();
    $till_date_leads = $till_date['leads_till_date'];

    $get_project = $this->db->query("SELECT p.project_id, p.project_name FROM `tbl_project` p INNER JOIN tbl_client c ON p.client_id = c.client_id WHERE  c.client_id = $id")->result();

    if((count($get_project) )> 0 ){
        foreach($get_project as $project) {
             $project_name = $project->project_name;
             $project_id = $project->project_id;
             $source_count = $this->db->query("SELECT COUNT(*) count_source, source FROM `tbl_leads` WHERE DATE(leads_update_on) = curdate() AND project_id=$project_id AND client_id=$id  GROUP BY source")->result();
             if((count($source_count) )> 0){
                ob_start();
                require_once($_SERVER['DOCUMENT_ROOT'].'/application/views/email_templates/daily_leads_cron.php');
                $body123 = ob_get_contents();
                ob_end_clean();

                //echo $body123;exit;

                $message = Swift_Message::newInstance("Daily Report")
                                        ->setFrom(array('abc@xyz.in' => 'abc'))
                                        ->setTo(array($c_email))
                                        ->setBody($body123, 'text/html')
                ;
                $mailer->send($message);
            }
    }
}
else {
    echo "else";
}
}

In daily_leads_cron.php there is html file with php foreachloop. I've tested the output of daily_leads_cron.php file with //echo $body123;exit; and its working fine.

The problem is that the receiver of mail gets two email instead of one and those mails are BLANK without any content. I've tested all loops and there is no any error. Anybody can tell me why this happening.