Fatal error: preg_match_all(): Argument #2

When I choose PDF Packing Slip and apply I now get the following:

Fatal error: preg_match_all(): Argument #2 ($subject) must be of type string, array given/home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/AbstractFrameReflower.php (529)#0 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/AbstractFrameReflower.php(529): preg_match_all() #1 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/AbstractFrameReflower.php(557): Dompdf\FrameReflower\AbstractFrameReflower->_parse_quotes() #2 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/AbstractFrameReflower.php(687): Dompdf\FrameReflower\AbstractFrameReflower->_parse_content() #3 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/AbstractFrameReflower.php(395): Dompdf\FrameReflower\AbstractFrameReflower->_set_content() #4 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/AbstractFrameReflower.php(437): Dompdf\FrameReflower\AbstractFrameReflower->get_min_max_child_width() #5 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/AbstractFrameReflower.php(458): Dompdf\FrameReflower\AbstractFrameReflower->get_min_max_content_width() #6 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameDecorator/AbstractFrameDecorator.php(921): Dompdf\FrameReflower\AbstractFrameReflower->get_min_max_width() #7 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/AbstractFrameReflower.php(396): Dompdf\FrameDecorator\AbstractFrameDecorator->get_min_max_width() #8 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/Block.php(937): Dompdf\FrameReflower\AbstractFrameReflower->get_min_max_child_width() #9 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/AbstractFrameReflower.php(458): Dompdf\FrameReflower\Block->get_min_max_content_width() #10 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameDecorator/AbstractFrameDecorator.php(921): Dompdf\FrameReflower\AbstractFrameReflower->get_min_max_width() #11 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/AbstractFrameReflower.php(420): Dompdf\FrameDecorator\AbstractFrameDecorator->get_min_max_width() #12 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/TableCell.php(143): Dompdf\FrameReflower\AbstractFrameReflower->get_min_max_child_width() #13 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/AbstractFrameReflower.php(458): Dompdf\FrameReflower\TableCell->get_min_max_content_width() #14 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameDecorator/AbstractFrameDecorator.php(921): Dompdf\FrameReflower\AbstractFrameReflower->get_min_max_width() #15 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/Cellmap.php(729): Dompdf\FrameDecorator\AbstractFrameDecorator->get_min_max_width() #16 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/Cellmap.php(604): Dompdf\Cellmap->calculate_column_widths() #17 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/Table.php(460): Dompdf\Cellmap->add_frame() #18 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/Table.php(331): Dompdf\FrameReflower\Table->get_min_max_width() #19 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameDecorator/AbstractFrameDecorator.php(913): Dompdf\FrameReflower\Table->reflow() #20 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/Block.php(865): Dompdf\FrameDecorator\AbstractFrameDecorator->reflow() #21 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameDecorator/AbstractFrameDecorator.php(913): Dompdf\FrameReflower\Block->reflow() #22 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameReflower/Page.php(142): Dompdf\FrameDecorator\AbstractFrameDecorator->reflow() #23 /home/seedsave/public_html/wp-content/plugins/civicrm/civicrm/vendor/dompdf/dompdf/src/FrameDecorator/AbstractFrameDecorator.php(913): Dompdf\FrameReflower\Page->reflow() #24 /home/seedsave/public_html/wp-content/plugins/woocommerce-pdf-invoices-packing-slips/vendor/dompdf/dompdf/src/Dompdf.php(808): Dompdf\FrameDecorator\AbstractFrameDecorator->reflow() #25 /home/seedsave/public_html/wp-content/plugins/woocommerce-pdf-invoices-packing-slips/includes/makers/class-pdf-maker.php(54): Dompdf\Dompdf->render() #26 /home/seedsave/public_html/wp-content/plugins/woocommerce-pdf-invoices-packing-slips/includes/documents/abstract-wcpdf-order-document.php(1027): WPO\WC\PDF_Invoices\Makers\PDF_Maker->output() #27 /home/seedsave/public_html/wp-content/plugins/woocommerce-pdf-invoices-packing-slips/includes/documents/abstract-wcpdf-order-document.php(1093): WPO\WC\PDF_Invoices\Documents\Order_Document->get_pdf() #28 /home/seedsave/public_html/wp-content/plugins/woocommerce-pdf-invoices-packing-slips/includes/class-wcpdf-main.php(568): WPO\WC\PDF_Invoices\Documents\Order_Document->output_pdf() #29 /home/seedsave/public_html/wp-includes/class-wp-hook.php(324): WPO\WC\PDF_Invoices\Main->generate_document_ajax() #30 /home/seedsave/public_html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters() #31 /home/seedsave/public_html/wp-includes/plugin.php(517): WP_Hook->do_action() #32 /home/seedsave/public_html/wp-admin/admin-ajax.php(192): do_action() #33 {main}

The page I need help with: [log in to see the link]