Checkout orders doesnt work

Hello,
recently my checkout doesnt work at woocommerce this theme. It worked few days earlier, but now, when someone try to buy something, it doesnt work, you cant send the order. Is this theme the problem? is it too old? How can i fix this please? ??
wp debug
Deprecated: Function create_function() is deprecated in /home/u547859720/domains/kaiobchod.com/public_html/wp-content/themes/holidayshop/functions.php on line 335

line: add_filter(‘loop_shop_per_page’, create_function(‘$cols’, ‘return ‘ . absint(get_theme_mod(‘archive_number_products’, 24)) . ‘;’), 20);

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