If you are registering with a new device then you have to add UDID of your device. Follow these steps to add the UDID:
- Open your Apple developer account and click on All under the Devices section.
- Click on the + sign. You see a window as such:
![](//cdn.storehippo.com/s/573db3149f0d58741f0cc63b/ms.files/uploads/59a957d1a65220f03b6a2859/screencapture-developer-apple-account-ios-device-create-1504270016076.png)
- Add the name of your device and the associated UDID for it.
- Click on the Continue button to complete your device registration.
To fetch the UDID of your device please refer to the following links:
https://www.innerfence.com/howto/find-iphone-unique-device-identifier-udid
http://whatsmyudid.com/
http://get.udid.io/