Argument Exception: GetComponent requires that the requested component 'PlayerInput' derives from MonoBehaviour or Component or is an interface

I'm trying to make a door that you can interact with using RayCast and the Animator. Before starting the game everythings seems ok, but when I click start these 2 errors pop up:

GetComponent requires that the requested component 'PlayerInput' derives from MonoBehaviour or Component or is an interface. NullReferenceException: Object reference not set to an instance of an object PlayerInteract.Update () (at Assets/Scripts/Player/PlayerInteract.cs:37)

Here is the code for both scripts:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class PlayerInteract : MonoBehaviour
{
private Camera cam;
[SerializeField]
private float distance = 3f;
[SerializeField]
private LayerMask mask;
private PlayerUI playerUI;
private PlayerInput playerInput;

void Start()
{
    cam = GetComponent<PlayerLook>().cam;
    playerUI = GetComponent<PlayerUI>();
    playerInput = GetComponent<PlayerInput>();
}

// Update is called once per frame
void Update()
{
    playerUI.UpdateText(string.Empty);

    Ray ray = new Ray(cam.transform.position, cam.transform.forward);
    Debug.DrawRay(ray.origin, ray.direction * distance);
    RaycastHit hitInfo;

    if(Physics.Raycast(ray, out hitInfo, distance, mask))
    {
        if(hitInfo.collider.GetComponent<Interactable>()!= null)
        {
            Interactable interactable = hitInfo.collider.GetComponent<Interactable>();
            playerUI.UpdateText(interactable.promptMessage);
            if (playerInput.OnFoot.Interact.triggered)
            {
                interactable.BaseInteract();
            }
        }
    }
}
}

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class PlayerInteract : MonoBehaviour
{
private Camera cam;
[SerializeField]
private float distance = 3f;
[SerializeField]
private LayerMask mask;
private PlayerUI playerUI;
private PlayerInput playerInput;

void Start()
{
    cam = GetComponent<PlayerLook>().cam;
    playerUI = GetComponent<PlayerUI>();
    playerInput = GetComponent<PlayerInput>();
}

// Update is called once per frame
void Update()
{
    playerUI.UpdateText(string.Empty);

    Ray ray = new Ray(cam.transform.position, cam.transform.forward);
    Debug.DrawRay(ray.origin, ray.direction * distance);
    RaycastHit hitInfo;

    if(Physics.Raycast(ray, out hitInfo, distance, mask))
    {
        if(hitInfo.collider.GetComponent<Interactable>()!= null)
        {
            Interactable interactable = hitInfo.collider.GetComponent<Interactable>();
            playerUI.UpdateText(interactable.promptMessage);
            if (playerInput.OnFoot.Interact.triggered)
            {
                interactable.BaseInteract();
            }
        }
    }
}
}