iPhone 16 Pro Max stuck during setup

My brand new iPhone 16 Pro Max got stuck while I was setting up (transferring data from my old phone 12 Pro max). The phone tried updating the new iOS and never completed for more than an hour. I am trying to reset the phone by briefly pressing volume up and then volume down followed by side upper button. It shows the keypad and the keypad disappears immediately also the 'Slide to power off' appears for less than a second and goes off. However, the display is on with 'Hello' messages in all the languages and the phone is getting hot. Not able to power off or reset.

Any advice? Thank you.

[Re-Titled by Moderator]