Set programmatically product sale price and cart item prices in Woocommerce 3

Question

This is the continuation of : Set product sale price programmatically in WooCommerce 3

The answer works, however once a user adds the product to cart, the old price stil

Answer 1

The accepted answer did not work for me. Here is what worked:

function get_active_price($price, $product) {
        if ($product->is_on_sale()) {
            return $product->get_sale_price();
        }
        return $product->get_regular_price();
    }

add_filter('woocommerce_product_get_price', 'get_active_price'));

This worked with custom sale and regular prices.