Fatal error: “get_language_attributes”

Hiho,

suddenly, the invoices are not generated any more, I receive the following error:

Fatal error: WPO\IPS\Documents\OrderDocument::get_language_attributes(): Return value must be of type string, null returned

/www/htdocs/XXXXXX/dev.dierakete.com/wp-content/plugins/woocommerce-pdf-invoices-packing-slips/includes/Documents/OrderDocument.php (980)#0 /www/htdocs/XXXXXX/dev.dierakete.com/wp-content/plugins/woocommerce-pdf-invoices-packing-slips/includes/Documents/OrderDocument.php(989): WPO\IPS\Documents\OrderDocument->get_language_attributes() #1 /www/htdocs/XXXXXX/dev.dierakete.com/wp-content/plugins/woocommerce-pdf-invoices-packing-slips/templates/Simple/html-document-wrapper.php(3): WPO\IPS\Documents\OrderDocument->language_attributes() #2 /www/htdocs/XXXXXX/dev.dierakete.com/wp-content/plugins/woocommerce-pdf-invoices-packing-slips/includes/Documents/OrderDocument.php(1597): include(‘/www/htdocs/v13…’) #3 /www/htdocs/XXXXXX/dev.dierakete.com/wp-content/plugins/woocommerce-pdf-invoices-packing-slips/includes/Documents/OrderDocument.php(1533): WPO\IPS\Documents\OrderDocument->render_template(‘/www/htdocs/v13…’, Array) #4 /www/htdocs/XXXXXX/dev.dierakete.com/wp-content/plugins/woocommerce-pdf-invoices-packing-slips/includes/Documents/OrderDocument.php(1457): WPO\IPS\Documents\OrderDocument->wrap_html_content(‘\n\n<table class=…’) #5 /www/htdocs/XXXXXX/dev.dierakete.com/wp-content/plugins/woocommerce-pdf-invoices-packing-slips/includes/Documents/OrderDocument.php(1407): WPO\IPS\Documents\OrderDocument->get_html() #6 /www/htdocs/XXXXXX/dev.dierakete.com/wp-content/plugins/woocommerce-pdf-invoices-packing-slips/includes/Documents/OrderDocument.php(1474): WPO\IPS\Documents\OrderDocument->get_pdf() #7 /www/htdocs/XXXXXX/dev.dierakete.com/wp-content/plugins/woocommerce-pdf-invoices-packing-slips/includes/Main.php(533): WPO\IPS\Documents\OrderDocument->output_pdf(‘inline’) #8 /www/htdocs/v133850/dev.dierakete.com/wp-includes/class-wp-hook.php(324): WPO\IPS\Main->generate_document_ajax(”) #9 /www/htdocs/XXXXXX/dev.dierakete.com/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(”, Array) #10 /www/htdocs/v133850/dev.dierakete.com/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #11 /www/htdocs/XXXXXX/dev.dierakete.com/wp-admin/admin-ajax.php(192): do_action(‘wp_ajax_generat…’) #12 {main}

I checked for any wrong / old settings and also re-saved the current ones, but still not working. The overall screen shows “parse error”. I tried debug mode, but no further infos given. Also I use the default templates, just added the logo via settings. Also deleted cache and stuff…

Any ideas? Thank you in advance

Greetings

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