foreach($_SESSION['cart'] as $key=>$item) {
                        if($index == $item['index']) $realqty = $realqty -1; else $realqty = $item['qty'] - 1;
                        mysqli_query($conn, "UPDATE items SET qty = '".$realqty."' WHERE product_index = '".$item['index']."';");
                        $index = $item['index'];
                    }