Add Related Products to Customer EMail

Hello there,
I have added this code to the functions.php of my child theme to add related products to customer emails with a shortcode in the template. The code used to work until the latest WC / WP update. Do you know why it isn’t working anymore?

This is the code:

// product suggestion in order mail
function order_mail_product_suggestion($atts) {
$atts=shortcode_atts(
    array(
        'id' => '',
    ), $atts, 'order_mail_product_suggestion');
$orderId = esc_attr($atts['id']);
$order = wc_get_order( (int)$orderId );
$items = $order->get_items();
$cat = array();
$pid = array();
foreach ( $items as $item ) {
    $pid[] = $item->get_product_id();
    $terms = wp_get_post_terms($item->get_product_id(),'product_cat',array('fields'=>'ids'));
    foreach ( $terms as $term ) {
        $cat[] = $term;
    }
}
$uniuqcat = array_unique($cat);
$uniuqpid = array_unique($pid);
$html = '';
$args = array(
    'post_type'             => 'product',
    'stock'                 => 1,
    'post_status'           => 'publish',
    'ignore_sticky_posts'   => 1,
    'posts_per_page'        => '20',
    'tax_query'             => array(
        array(
            'taxonomy'      => 'product_cat',
            'field' => 'term_id',
            'terms'         => implode(',', $uniuqcat),
            'operator'      => 'IN'
        ),
        array(
            'taxonomy'      => 'product_visibility',
            'field'         => 'slug',
            'terms'         => 'exclude-from-catalog',
            'operator'      => 'NOT IN'
        )
    )
);
$loop = new WC_Product_Query($args);
$products = $loop->get_products();
if ($products) {
    $html .= '<div id="suggestion" style="padding: 20px 0;border-top: 1px solid #eee;">';
        $html .= '<h2 style="text-align: center;font-weight: 400;color: #000;">PLUS, MORE THINGS YOU MAY LIKE</h2>';
        $html .= '<table style="width: 100%;table-layout: fixed;border-collapse: collapse;">';
            $html .= '<tbody>';
                $html .= '<tr>';
                        $i=0;
                        foreach ( $products as $product ) {
                            if (in_array($product->get_id(), $pid)) {
                                continue;
                            }
                            $html .= '<td align="center" style="padding: 5px;border: 1px solid #eee;">';
                            if (has_post_thumbnail( $product->get_id() )) {
                                $html .= get_the_post_thumbnail($product->get_id(), 'shop_catalog');
                            } else {
                                $html .= '<img src="'.woocommerce_placeholder_img_src().'" alt="Placeholder" width="300px" height="300px" />';
                            }
                            $html .= '<h3><a style="color: #000;font-weight: normal;text-decoration: none;font-size: 13px;text-align: center;display: block;line-height: 16px;" href="'.get_permalink( $product->get_id() ).'">'.esc_attr($product->get_title() ? $product->get_title() : $product->get_id()).'</a></h3>';
                            $html .= '<p><a style="font-weight: normal;text-decoration: none;display: block;margin: 0 auto;max-width: 72px;padding: 4px 9px;text-align: center;background-color: #000;color: #fff;font-size: 13px;" href="'.get_permalink( $product->get_id() ).'" class="shop-now">Shop Now</a></p>';
                            $i++;
                            if($i==4) break;
                        }
                $html .= '</tr>';
            $html .= '</tbody>';
        $html .= '</table>';
    $html .= '</div>';
}
// now return the preapred html
return $html;
}
// register shortcode add_shortcode('email_product_suggestion', 'order_mail_product_suggestion');

However, now I get a fatal error with the same code
Fatal error: Uncaught Error: Call to a member function get_items() on boolean in /home/beats247/public_html/2020/wp-content/themes/martfury-child/functions.php:186 Stack trace: #0 /home/beats247/public_html/2020/wp-includes/shortcodes.php(343): order_mail_product_suggestion(Array, ”, ’email_product_s…’) #1 [internal function]: do_shortcode_tag(Array) #2 /home/beats247/public_html/2020/wp-includes/shortcodes.php(218): preg_replace_callback(‘/\\[(\\[?)(email_…’, ‘do_shortcode_ta…’, ‘[email_product_…’) #3 /home/beats247/public_html/2020/wp-content/plugins/kadence-woocommerce-email-designer/templates/woo/emails/customer-completed-order.php(69): do_shortcode(‘[email_product_…’) #4 /home/beats247/public_html/2020/wp-content/plugins/woocommerce/includes/wc-core-functions.php(344): include(‘/home/beats247/…’) #5 /home/beats247/public_html/2020/wp-content/plugins/woocommerce/includes/wc-core-functions.php(363): wc_get_template(’emails/customer…’, Array, ”, ”) #6 /home/beats247/public_html/2020/wp-content/plugins/w in /home/beats247/public_html/2020/wp-content/themes/martfury-child/functions.php on line 186

This is line 186:
$items = $order->get_items();

What needs to be changed in the code so it’s working again? Thanks!