ошибка 504 - это сервер не успевает обработать все запросы.
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[Tue Jul 31 11:21:13.079630 2018] [cgi:error] [pid 16593] [client 46.174.167.85:35022] AH01215: order_comments was called incorrectly. Order properties should not be accessed directly. Backtrace: do_action('wp_ajax_woocommerce_mark_order_status'), WP_Hook->do_action, WP_Hook->apply_filters, WC_AJAX::mark_order_status, WC_Order->update_status, WC_Order->save, WC_Order->status_transition, do_action('woocommerce_order_status_completed'), WP_Hook->do_action, WP_Hook->apply_filters, WC_Emails::send_transactional_email, do_action_ref_array, WP_Hook->do_action, WP_Hook->apply_filters, WC_Email_Customer_Completed_Order->trigger, WC_Email->get_content, WC_Email_Customer_Completed_Order->get_content_html, wc_get_template_html, wc_get_template, include('/plugins/woocommerce/templates/emails/customer-completed-order.php'), do_action('woocommerce_email_customer_details'), WP_Hook->do_action, WP_Hook->apply_filters, WC_Emails->email_addresses, wc_get_template, do_action('woocommerce_after_template_part'), WP_Hook->do_action, WP_Hook->apply_filters, saphali_lite->email_pickup_location, WC_Abstract_Legacy_Order->__get, wc_doing_it_wrong. This message was added in version 3.0.: /php71bin/velanpack/php-cgi, referer:
http://www.velan-pack.com/wp-admin/edit.php?post_type=shop_order&all_posts=1
[Tue Jul 31 11:21:21.180235 2018] [cgi:error] [pid 17501] [client 93.77.133.97:32858] Script timed out before returning headers: php-cgi, referer:
http://www.velan-pack.com/checkout/
[Tue Jul 31 11:21:44.589759 2018] [cgi:error] [pid 17827] [client 46.174.167.85:37574] AH01215: order_comments was called incorrectly. Order properties should not be accessed directly. Backtrace: require('wp-blog-header.php'), require_once('wp-includes/template-loader.php'), do_action('template_redirect'), WP_Hook->do_action, WP_Hook->apply_filters, WC_AJAX::do_wc_ajax, do_action('wc_ajax_checkout'), WP_Hook->do_action, WP_Hook->apply_filters, WC_AJAX::checkout, WC_Checkout->process_checkout, WC_Checkout->process_order_payment, WC_Gateway_Cheque->process_payment, WC_Order->update_status, WC_Order->save, WC_Order->status_transition, do_action('woocommerce_order_status_pending_to_on-hold'), WP_Hook->do_action, WP_Hook->apply_filters, WC_Emails::send_transactional_email, do_action_ref_array, WP_Hook->do_action, WP_Hook->apply_filters, WC_Email_New_Order->trigger, WC_Email->get_content, WC_Email_New_Order->get_content_html, wc_get_template_html, wc_get_template, include('/plugins/woocommerce/templates/emails/admin-new-order.php'), do_action('woocommerce_email_customer_details'), WP_Hook->do_action, WP_Hook->apply_filters, WC_Emails->email_addresses, wc_get_template, do_action('woocommerce_after_template_part'), WP_Hook->do_action, WP_Hook->apply_filters, saphali_lite->email_pickup_location, WC_Abstract_Legacy_Order->__get, wc_doing_it_wrong. This message was added in version 3.0.: /php71bin/velanpack/php-cgi, referer:
http://www.velan-pack.com/checkout/