Shopping CartShop

Fatal error: Uncaught mysqli_sql_exception: Unknown column 'cart.date_added' in 'ORDER BY' in /home/discyqfz/public_html/classes/Config.class.php:43 Stack trace: #0 /home/discyqfz/public_html/classes/Config.class.php(43): mysqli->prepare() #1 /home/discyqfz/public_html/classes/Frontend.class.php(902): Config->selectQuery() #2 /home/discyqfz/public_html/cart.php(42): Frontend->shoppingCartItems() #3 {main} thrown in /home/discyqfz/public_html/classes/Config.class.php on line 43