Name 'InputSystem' does not exist in the namespace 'UnityEngine'

I have installed the new InputSystem package in my Unity project via the package manager. I have set the input to "new inputsystem" in the Unity Player Settings. I have quit and restarted both Unity and VS Code.

But when I try to use the inputsystem in VS Code, I immediately get an error:

Code (CSharp):

1. using UnityEngine;
2. using System.Collections;
3. using UnityEngine.InputSystem;              // <-error
4. using UnityEngine.InputSystem.Controls;     // <-error

The type or namespace name 'InputSystem' does not exist in the namespace 'UnityEngine' (are you missing an assembly reference?) [Assembly-CSharp]

Why can't I reference the new inputsystem from code?

 

https://forum.unity.com/threads/unityengine-inputsystem-not-found.945820/

 

plaese help guys