If you registered 7 or less volunteers, since you haven't been verified yet, maybe you could add your child with corrected birthdate in as an additional volunteer. Then go to Hands-on Site and click on Change / Cancle the Opportunity that I have signed up for. Then click on the opportunity. Then select (check) the child with the corrected birthdate and deselect (uncheck) the child with the wrong birthdate. The child with the incorrect birthday will just never "sign-up" for an opportunity. I'm not sure if it will matter or not, but at least you'll have the peace of mind that the data connected to the voucher bar code is correct. DISclaimer: I'm not sure if this will work...just an idea...may be safer to call Disney.