Fatal error

Error Details
=============
An error of type E_ERROR was caused in line 181 of the file /home/notation/www/www/wp-content/plugins/wc-serial-numbers/includes/admin/class-wc-serial-numbers-admin-metaboxes.php. Error message: Uncaught Error: Call to a member function get_id() on null in /home/notation/www/www/wp-content/plugins/wc-serial-numbers/includes/admin/class-wc-serial-numbers-admin-metaboxes.php:181
Stack trace:
#0 /home/notation/www/www/wp-includes/class-wp-hook.php(287): WC_Serial_Numbers_Admin_MetaBoxes->order_itemmeta(28124, Object(WC_Order_Item_Shipping), NULL)
#1 /home/notation/www/www/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(NULL, Array)
#2 /home/notation/www/www/wp-includes/plugin.php(478): WP_Hook->do_action(Array)
#3 /home/notation/www/www/wp-content/plugins/woocommerce/includes/admin/meta-boxes/views/html-order-shipping.php(50): do_action(‘woocommerce_aft…’, 28124, Object(WC_Order_Item_Shipping), NULL)
#4 /home/notation/www/www/wp-content/plugins/woocommerce/includes/admin/meta-boxes/views/html-order-items.php(81): include(‘/home/notation/…’)
#5 /home/notation/www/www/wp-content/plugins/woocommerce/includes/admin/meta-boxes/class-wc-meta-box-order-items.php(41): include(‘/home/notation/…’

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