Character is not able to move by using (A , S , D) in unity

Question

Today I watched an video on how to make movement in youtube (https://www.youtube.com/watch?v=bzheMJQVtBI) but the movement occur only when I press W key or change the direction not by using (A, S, D keys) anybody idea how to solve this problem.

AgentMovemnt.cs

using UnityEngine;

namespace SVS
{
    public class AgentMovement : MonoBehaviour
    {
        CharacterController controller;
        Animator animator;
        public float rotationSpeed, movementSpeed, gravity = 20;
        Vector3 movementVector = Vector3.zero;
        private float desiredRotationAngle = 0;

        private void Start()
        {
            controller = GetComponent<CharacterController>();
            animator = GetComponent<Animator>();
        }

        public void HandleMovement(Vector2 input)
        {
            if (controller.isGrounded)
            {
                if(input.y > 0)
                {
                    movementVector = transform.forward * movementSpeed;
                }
                else
                {
                    movementVector = Vector3.zero;
                    animator.SetFloat("move", 0);
                }
            }
        }

        public void HandleMovementDirection(Vector3 direction)
        {
            desiredRotationAngle = Vector3.Angle(transform.forward, direction);
            var crossProduct = Vector3.Cross(transform.forward, direction).y;
            if (crossProduct < 0)
            {
                desiredRotationAngle *= -1;
            }
        }

        private void RotateAgent()
        {
            if(desiredRotationAngle > 10 || desiredRotationAngle < -10)
            {
                transform.Rotate(Vector3.up * desiredRotationAngle * rotationSpeed * Time.deltaTime);
            }
        }

        private float SetCorrectAnimation()
        {
            float currentAnimationSpeed = animator.GetFloat("move");
            
            if(desiredRotationAngle > 10 || desiredRotationAngle < -10)
            {
                if(currentAnimationSpeed < 0.2f)
                {
                    currentAnimationSpeed += Time.deltaTime * 2;
                    currentAnimationSpeed = Mathf.Clamp(currentAnimationSpeed, 0, 0.2f);
                }
                animator.SetFloat("move", currentAnimationSpeed);
            }
            else
            {
                if (currentAnimationSpeed < 1)
                {
                    currentAnimationSpeed += Time.deltaTime * 2;
                }
                else
                {
                    currentAnimationSpeed = 1;
                }
                animator.SetFloat("move", currentAnimationSpeed);
            }
            return currentAnimationSpeed;
        }

        private void Update()
        {
            if (controller.isGrounded)
            {
                if (movementVector.magnitude > 0)
                {
                    var animationSpeedMultiplier = SetCorrectAnimation();
                    RotateAgent();
                    movementVector *= animationSpeedMultiplier;
                }
            }
            movementVector.y -= gravity;
            controller.Move(movementVector * Time.deltaTime);
        }
    }
}

AgentController.cs

using UnityEngine;

namespace SVS
{
    public class AgentController : MonoBehaviour
    {
        IInput input;
        AgentMovement movement;

        private void OnEnable()
        {
            input = GetComponent<IInput>();
            movement = GetComponent<AgentMovement>();
            input.OnMovementDirectionInput += movement.HandleMovementDirection;
            input.OnMovementInput += movement.HandleMovement;
        }

        private void OnDisable()
        {
            input.OnMovementDirectionInput -= movement.HandleMovementDirection;
            input.OnMovementInput -= movement.HandleMovement;
        }
    }
}

PlayerInput.cs

using System;
using UnityEngine;

namespace SVS
{
    public class PlayerInput : MonoBehaviour, IInput
    {
        public Action<Vector2> OnMovementInput { get; set; }
        public Action<Vector3> OnMovementDirectionInput { get; set; }

        private void Start()
        {
            //Cursor.lockState = CursorLockMode.Locked;
        }

        private void Update()
        {
            GetMovementInput();
            GetMovementDirection();
        }

        private void GetMovementDirection()
        {
            var cameraForewardDIrection = Camera.main.transform.forward;
            Debug.DrawRay(Camera.main.transform.position, cameraForewardDIrection * 10, Color.red);
            var directionToMoveIn = Vector3.Scale(cameraForewardDIrection, (Vector3.right + Vector3.forward));
            Debug.DrawRay(Camera.main.transform.position, directionToMoveIn * 10, Color.blue);
            OnMovementDirectionInput?.Invoke(directionToMoveIn.normalized);
        }

        private void GetMovementInput()
        {
            Vector2 input = new Vector2(Input.GetAxis("Horizontal"), Input.GetAxis("Vertical"));
            OnMovementInput?.Invoke(input);
        }
    }
}

IInput.cs

using System;
using UnityEngine;

namespace SVS
{
    public interface IInput
    {
        Action<Vector3> OnMovementDirectionInput { get; set; }
        Action<Vector2> OnMovementInput { get; set; }
    }
}

Answer 1

//Upward movement - W

     if(Input.GetKey(KeyCode.W))
     {
        print("w");
        transform.Translate(Vector3.up * Time.deltaTime * 1);
       }

//Move down - S

 if(Input.GetKey(KeyCode.S))
{
  print("s");
  transform.Translate(Vector3.down * Time.deltaTime * 1);
 }

//Move to the left - A

    if(Input.GetKey(KeyCode.A))
   {
      print("a");
      transform.Translate(Vector3.left * Time.deltaTime * 1);
    }

//move right - D

  if(Input.GetKey(KeyCode.D))
  {
    print("d");
    transform.Translate(Vector3.right * Time.deltaTime * 1);
  }

This is some introduction about unity mobile hope it can help you thank you