When selecting a tariff and activating iPhone in the United Kingdom, iTunes will need to validate your billing address.
If iTunes is unable to find a match for your address, please check that your address is registered with Royal Mail. If your address isn't registered, perhaps because you live in a new property, you'll need to email your correct name and address to addressmaintenance@royalmail.com requesting it be added to their database (unfortunately, O2 can't do this on your behalf).
Once your address is added to Royal Mail's database, please let O2 know by sending an email to o2address@o2.com. As soon as O2 have updated their systems (usually within 48 hours), you'll be able to restart the activation process.
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