pero cuando agregué una tabla que se crea conforme a los datos que regresa un consulta ya no descarga el PDF

public function sendAsPDF($filename){
require_once("dompdf/dompdf_config.inc.php");
$headHtml= "<!doctype html>
<html>
<head>
<?php use_stylesheet('style.css') ?>
</head>
<body> ";
$finHtml =stripslashes('</body> </html>');
$tableinit="<table border=2>";
$tablefin ="</table>";
$cont.=$headHtml.$tableinit;
$encabezado= 'Campaing';
$cont.=stripslashes('<th scope="col">Columna 1</th>');
$cont.=stripslashes('<th scope="col"></th>');
$cont.=stripslashes('<th scope="col">Columna 2</th>');
$cont.=stripslashes('<th scope="col"></th>');
$cont.=stripslashes('<th scope="col">Columna 3</th>');
foreach ($this->getAll() as $row) {
$cont.=stripslashes('<tr>');
foreach ($row as $v) {
$cont.=stripslashes('<td>');
$cont.=$v;
$cont.=stripslashes('<td>');
}
$cont.=stripslashes('</tr>');
}
$cont.=$tablefin.$finHtml;
echo $cont;
$dompdf = new DOMPDF();
$dompdf->load_html($cont);
//$dompdf->set_paper('letter','landscape');
$dompdf->set_paper("letter", $orientation = "landscape");
$dompdf->render();
$dompdf->stream("reporte.pdf");//cambiar nombre por el que se genera con la fecha
}