Iphone 6s stuck on recovery screen. Please help!

I have an Iphone 6s and it is stuck on recovery screen, when "Verifying iPhone restore..." on iTunes.

I have followed the instruction on this post: If you can't update or restore your iPhone, iPad, or iPod touch - Apple Support.

When it reaches the "iPhone Recovery Mode" it stuck right there.

I do not know which is the latest IOS. Usually I perform the updates as soon as I am notified by Apple.

Please help!