How do I change my customer's email address?
To update the email address for a customer, go to the Order Summary tab and then to the Customer Info section.
Click on the Add Alternate Email button and enter in the new email address. You will now see this new email address in the Alternate Email section.

To resend the order email to the new email address, click on the Resend Email button.
🚨Please note: Adding an Alternate Email for your customer will not allow them to use that email to log into the order if they have used a different email to open the order previously. They will only be able to use the Alternate Email when opening for the first time. Please see the article here for more on how that works.