Hey there, @hollyday. Thanks for taking the time to reach out to the Shopify Community regarding your situation with your date of birth. It's great to meet you!
So for an information change like this, you're going to want to reach out to the Live Support Team to request this information change. You can use this link to get in touch with them. Sending them an email is going to be a fine way to have this information tweak request go through. Someone will follow-up with you regarding the request as soon as they can once you reach out.
Is this a new business that you're looking to open? I'd love to hear more about your goals!
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