We process and ship orders as quickly as possible, so there's a very limited window to make changes. Once an order moves into processing, we're no longer able to edit or cancel it. At that point, our fulfillment facility has already packed it and can't pull individual packages from an active shipment run.
If you need to make a change, contact us at help@dailies.co right away, and we'll do our best to help before it reaches that stage.