Local regulation requires Twilio to have an address on file for your account to purchase this phone number. You must add an address that specifies the end user's location using our API or account portal. Alternatively, you can provision a phone number that does not require an address by using Basic List Filters on the AvailablePhoneNumbers resource. If you received this error when trying to transfer a phone number to a subaccount or between subaccounts, please ensure that the subaccount has the correct address on file.