Days to conversion in Sales Ecommerce Is not updated correctly

Days to conversion in the Ecommerce sales is not getting reflected properly. The user with a new user id has visited the first time and made Ecommerce order and it is not getting reflected in 0 days. A user who visited 23 days ago has made the eCommerce orders but it is getting updated in days 30-60 in days to conversion sales but the visited has visited only 23 days ago first.