problem with scripting movement

Hey, so I've followed a guide by code monkey where he shows how to script jumping and movement. All the jumping part is ok (although I had to change it a little to work, I don't know why) but there is a problem with moving, it doesn't do that at all. using System; using System.Collections; using System.Collections.Generic; using UnityEngine;

public class Payer : MonoBehaviour {

 Rigidbody2D rigid2d;
 public Func<BoxCollider2D> bCollider2D;
 float jumpVelocity = 50f;
 public BoxCollider2D bCollider2d;
 public RaycastHit2D raycastHit2d;
 public LayerMask platformsLayerMask;
 float moveSpeed = 40f;



 public void Start()
 {
     rigid2d = transform.GetComponent<Rigidbody2D>();
     bCollider2D = transform.GetComponent<BoxCollider2D>;

 }

 private void Update()
 {
     if (isGrounded() && Input.GetKeyDown(KeyCode.Space))
     {

         rigid2d.velocity = Vector2.up * jumpVelocity;
     }
 }
 private bool isGrounded()
 {
     RaycastHit2D raycastHit2d = Physics2D.BoxCast(bCollider2d.bounds.center, bCollider2d.bounds.size, 0f, Vector2.down, .1f, platformsLayerMask);
     Debug.Log(raycastHit2d.collider);
     return raycastHit2d.collider != null;
 }

 private void HandleMovement()
 {
     
     if (Input.GetKeyDown(KeyCode.A))
     {
         rigid2d.velocity = new Vector2(-moveSpeed, rigid2d.velocity.y);

     } else
     {
         if (Input.GetKeyDown(KeyCode.D))
         {
             rigid2d.velocity = new Vector2(+moveSpeed, rigid2d.velocity.y);

         } else
         {//no keys pressed
             rigid2d.velocity = new Vector2(0, rigid2d.velocity.y);
         }
     }
 }

}

Does anybody know what to do?

here is a link to yt channel if necessary, about 9:30 minute.

Edit: I forgot to add. Yes, my player is called Payer. I just thought it would be funny