Hello,
I’ve marked as best sellers when I add a product
Could you, please, tell me where you marked that? Because WooCommerce does not have the option to mark the product as a bestseller by default. Do you use any additional plugin for these purposes? Provide a screenshot of the option that you used.
By default, best seller products are top sold products on your site and you can’t control it because it’s based on sales.
Regards