The code to clear the cart:
$eCart1->ClearCart();
is using a cart named eCart1, your cart is named BNB. the code should be:
$BNB->ClearCart();
Try using this code instead:
<?php
// Initialize the session.
// If you are using session_name("something"), don't forget it now!
@session_start();
// Unset all of the session variables.
$_SESSION = array();
// If it's desired to kill the session, also delete the session cookie.
// Note: This will destroy the session, and not just the session data!
if (isset($_COOKIE[session_name()])) {
@setcookie(session_name(), '', time()-42000, '/');
}
// Finally, destroy the session.
session_destroy();
?>