Question XROrigin Namespace Error?

Trying to declare XROrigin like so:

private XROrigin xROrigin;

But am met with the following error:
Assets\CharacterMoveHelp.cs(8,13): error CS0246: The type or namespace name 'XROrigin' could not be found (are you missing a using directive or an assembly reference?)

I am genuinely stumped. I have the XR toolkit in the script and have called it properly in all other aspects of the script. Any ideas? See the attached image for the full script.

 

https://docs.unity.cn/Packages/com.unity.xr.core-utils@2.0/api/Unity.XR.CoreUtils.XROrigin.html

As seen here you are using the wrong namespace. It's using xr core utils

 

And where can I find the Package? Package Manager doesn't list it.

I have added it manually to the packages manifest.json but this can't be the official way:

 

Add using Unity.XR.CoreUtils maybe.
Or properly link visual studio, so you can simply see what VS/Unity suggests as fix

 

This was the first I tried
Neither VS nor ReSharper suggest something that would resolve the problem.

 

Instead "XROrigin" use "ARSessionOrigin", this have the same parameters