Your customer wants to change their shipping address for a print-on-demand order:
As long as the order is not marked "in production," go to your TPOP dashboard / Orders and click on the order number "Details." On the next page, you will be able to edit the shipping information.
Your customer wants to change a product / size / color: In this case, it is necessary to cancel their order and then create a new one.
Note that if you modify the visuals of your products after the order has been placed, we will process the order with the initial visuals.