If you need to change your shipping address
There is a link in your order confirmation email that will let you cancel your order. Do that. It will also reload your shopping cart so you can check out again (with, presumably, your updated info). Your original purchase amount will be refunded to your original payment method.
We recommend canceling the incorrect order as the only 100% guaranteed way of preventing it from being shipped to the wrong address. If the link allows you to cancel, that means the order has not yet shipped out.
You can contact support with the updated info, and we can change it on our end if we see the message in time – but it's possible we might not catch it in time, as we are trying very hard to get packages out the door as quickly as possible. There can sometimes be delays while we work through the incoming message queue.
Once the order has shipped, we cannot modify the delivery address while the package is in transit. It's just not a thing that the mail allows.
If the package is headed to an old address, and you have mail forwarding set up from your old address to your new one, usually USPS will honor that. Outside the US, you can inquire with your local postal service or with the delivery service (whichever service we gave you a tracking number for) to see if they can make special delivery arrangements for you.
If the order is returned to sender because of a delivery problem, we can address the issue at that time. See returned packages.