Q: My new iphone is hanged with >slide to upgrade

After my new iphone 6s plus setup is done, the phone is hanged with the apple logo and cannot be powered off.  After it is reset, the phone showed Update Completed.Your iPhone was updated successfully. There are just a few more steps to follow, and then you're done! Continue.

After I press on Continue, it is a white screen with > slide to upgrade

and the phone is stuck here.