Most of the time, this is caused by a corrupted cache or an interrupted installation. The first thing to do is to restart your phone. If that doesn't help, you can clear cache/data by going to Settings > Apps > Android Setup/Android Setup Wizard > Storage, and then reboot. Also, ensure that Google Play Services is up to date. If the problem persists, you can try booting the phone in safe mode or, as a last resort, do a factory reset.