there is no get_sale_price()

Hi, in my custom theme I have a custom badge with percent discount, which works on
$product->get_regular_price();
and
$product->get_sale_price();
On this two variables is calculated percent discount. But products discounted with your plugin (PRO Version) doesn’t have this variables.
How I can reach the regular price and sale price?
Or maybe just the percent calculated by plugin? In options there is variable, which can be used as suffix: {price_save_percent} – how I can use this in php code in theme?

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