You can add a new address by navigating to:
Account page (smiley icon)> Addresses > tap "Add new Address".
You can also add a new address during the photo submission flow, if you realize the recipient name /address is not in your saved settings while submitting your request.
Here's how:
Once you have submitted a photo and it has been recognized, tap "Add a new address or select from full list"
On the next screen, tap "New" to add a new address mid-submission.