When your new iPhone restarts you’ll go through the setup process again.Go to Settings > General > Reset > Erase all Content and Settings. Now that your new device is running the same OS version as your old device, reset it.If you are running an iOS beta on your old device, enroll your new device in the beta ( public, developer), restart, and update it. Go to Settings > General > Software Update. Power on your new iPhone and choose to set it up as a new device.Make a fresh backup of your old device to iCloud or iTunes as in the sections above.The solution is to set up your new iPhone as a new device, update it to match your old device, then erase it and go through setup again to restore your backup from your old device.
