i know my question will not be answered, but i will ask.
i want subtotal to be calculated without considering sale price, that is, to consider the regular price, i did a lot of searching on the net, but i didn't get an answer.
i think i need to change the calculation method, but i don't know where to start.
echo wc_price( $product->get_regular_price() * $item['quantity'] );
it is not used on the order viewing page because if the order is today and the price changes tomorrow, the new price will be displayed, not the price at the time of placing the order.