Face ID , true depth camera not working

Hi, and welcome to the Apple Community.

Re: "Face ID , true depth camera not working"

Seems Face ID works best with the most up-to-date software.

If you haven't already, you might want to try updating the iPad Pro to the latest iOS version

ie: settings > software update

or

use a computer to update the iPad Pro

Mac: Update software on your iPhone or iPad – Apple Support

PC: Update software on iPhone, iPad or iPod touch in iTunes on PC – Apple Support

When updating:

It is always a good idea to start by making a back-up of all that you have stored on your iPad Pro.

How to back up your iPhone, iPad, and iPod touch - Apple Support

Else:

Check Your Service and Support Coverage - Apple Support

or

if needed, speak or chat with the experts for advice: contact Apple Support.

All the best :-)