Basic Contact Form Fix (2 pages)

I have a basic PHP hotel site on a shared server. Contact Form and Booking Form (both just simple forms using this: $mail = $smtp->send($to, $headers, $body); if (PEAR::isError($mail)) { echo("<p>" . $mail->getMessage() . "</p>"); } else { echo("<p>Message successfully sent!</p>"); } This was working, it now still shows success but the emails never arrive. This URL (and the booking page) : [login to view URL] Thanks