Как избавиться от дергания перса при взаимодействии со стеной

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
 
public class dMovement : MonoBehaviour
{
    public isdoun buttonW;
    public isdoun3 buttonA;
    public isdoun2 buttonS;
    public isdoun4 buttonD; 
    public Animator ch_animator;
    public static int speed = 4; 
    public static int _speed; 
    public int rotation = 250;  
    public int jump = 5;         
    public GameObject player;
    public float speedMove;
    public float jumpPower;     
    private float gravityForce = 1f;
    private Vector3 moveVector;
    
    void Start(){
        
        ch_animator = GetComponent<Animator>();
    }
    void Update(){
        moveVector.y = gravityForce;
        
        
    if(Input.GetKey(KeyCode.W)||buttonW.isDown) 
  { 
  player.transform.position += player.transform.up * speed * Time.deltaTime; 
  ch_animator.SetBool("moveback", true);
  }
  else if(Input.GetKey(KeyCode.S)||buttonS.isDowne){
        player.transform.position -= player.transform.up * speed * Time.deltaTime;
        ch_animator.SetBool("movefront", true);
  }
  else if(Input.GetKey (KeyCode.A)||buttonA.isDow) 
  { 
  player.transform.position -= player.transform.right * speed * Time.deltaTime;
  ch_animator.SetBool("moveright", true);
  }
  else if(Input.GetKey (KeyCode.D)||buttonD.isDoww) 
  { 
  ch_animator.SetBool("moveleft", true);
  player.transform.position += player.transform.right * speed * Time.deltaTime;   
  }
 
  else{
      ch_animator.SetBool("moveleft", false);
      ch_animator.SetBool("movefront", false);
      ch_animator.SetBool("moveright", false);
      ch_animator.SetBool("moveback", false);
  }
  
     
    }
    
}

 player.transform.position -= player.transform.right * speed * Time.deltaTime;

void start()
{
   rb=GetComponent<RigidBody2D>
}
void Update()
{
   rb.velocity (Input.GetAxis("Horizontal") * speed * Time.deltaTime);
}