Is it correct that you added the two price columns yourself with a custom field columns?
WooCommerce does not just store the prices in the post meta table as you might think. It does more than that so you just can’t use these two fields as a custom field column.

Please notice that there is a column called price in the WooCommerce addon (business and developer license only) that allows you to use inline edit for both the regular and sales price in a WooCommerce way. It’s better to use this one instead of creating custom field columns that uses the keys ‘_price’, ‘_regular_price’ or ‘_sales_price’