How do I fix an incorrect order?

In Commerce7, you cannot edit an order after it’s been completed. We don’t have this functionality for a variety of reasons, including tax and compliance issues. 

That said, when an order has been processed incorrectly, you have to refund the order and re-add it. Depending on the order issues, you can either do a partial refund (i.e refund just shipping) or a full refund. Here is a link to documentation on How To Refund An Order.

To help speed up the process, you can duplicate the original order before refunding it. You can do this under Store > Orders > Click into the original order > Click more actions > Click duplicate order.