Update 13.1.2
My iPhone Started the update 13.1.2 on my iPhone but it won't finish and it is stuck now.
iPhone XS
Same problem. It remained stuck for almost 3hrs. Then I had a call with the support team, they made me force restarting it.
You have to press + vol button, then - vol button and press the power button until it shuts down and you see the apple sign again. Be aware that it will restore your iPhone. You'll have to set it up from beginning.