The name ‘Physics2d’ does not exist in the current context No se porque pasa eso. Alguien me puede ayudar? <code>using System.Collections...

The name ‘Physics2d’ does not exist in the current context No se porque pasa eso. Alguien me puede ayudar?

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


public class PlayerControler : MonoBehaviour 
{
       public float jumpForce = 6f; 
    private Rigidbody2D  rigidBody; 

    public LayerMask groundMask;

    void Awake()
    {
        rigidBody = GetComponent<Rigidbody2D>();
    }    
    // Start is called before the first frame update
    void Start()
    {
        
    }

    // Update is called once per frame
    void Update()
    {
         if(Input.GetKey(KeyCode.Space) || Input.GetMouseButtonDown(0)) 
         {
           Jump();
         }
    }

    void Jump()
    {
        if(IsTouchingTheGround()) 
        {
            rigidBody.AddForce(Vector2.up*jumpForce, ForceMode2D.Impulse);
        }
                
    }
      //Nos indica si el personaje esa o no tocando el suelo
    bool IsTouchingTheGround(){
        if (Physics2d.Raycast(this.transform.position,
                              Vector2.down,
                              1.5f,
                              groundMask)){
                                  //TODO: programar logica de contacto con el suelo 
                                  return true;
                              }else{
                                  //TODO:programar logica de no contacto
                                  return false;
                              }
    }
}