How to use non-MonoBehaviour class in a unity Script

I can't understand why when I use a method of the Colors class in PlayerMovement, the PlayerMovement component is disabled.

The class Colors is:

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class Colors
 {
     private Color[] color = new Color[3];
 
     public Colors()
     {
         color[0] = Color.red;
         color[1] = Color.blue;
         color[3] = Color.green;
     }
 
     public Color chooseRandomColor()
     {
         int index = Random.Range(0, 3);
         return color[index];
     }
 
     public bool areColorEquals(Color color1, Color color2)
     {
         if (color1 == color2)
             return true;
         else
             return false;
     }
 
 }

The class PlayerMovement is:

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class PlayerMovement : MonoBehaviour
 {
     Colors playerColor = new Colors();
 
     //componenti
     private Rigidbody2D playerRb;
     private SpriteRenderer playerSpriteRenderer;
 
     [Header("Movimento")]
     [SerializeField] private float horizontalSpeed;
     private float horizontalInput;
 
 
     // Start is called before the first frame update
     void Awake()
     {
         playerRb = gameObject.GetComponent<Rigidbody2D>();
         playerSpriteRenderer = gameObject.GetComponent<SpriteRenderer>();
 
         playerSpriteRenderer.color = playerColor.chooseRandomColor();
 
     }
 
     private void Start()
     {    }
 
     private void Update()
     {
         horizontalInput = Input.GetAxisRaw("Horizontal");
     }
 
     // Update is called once per frame
     void FixedUpdate()
     {
         playerRb.MovePosition(playerRb.position + Vector2.right 
                             * horizontalInput * horizontalSpeed * Time.fixedDeltaTime);
     }
     private void OnTriggerEnter2D(Collider2D collision)
     {
         Debug.Log("Morto");
         if (collision.gameObject.tag == "Block")
         {
             Object.Destroy(gameObject, 0f);
         }
     }
 }