How does the player jump while on the ladder?

hi everyone. I prepared a simple scene for my game that I plan to do. So it's not quite finished yet. but i got stuck on one thing. The character does not jump while on the ladder. I think the problem is caused by gravityscale. Gravity value is 0 when I'm on the ladder. I couldn't do it no matter what I tried. I hope you know a way :) thanks.

here is code:

using UnityEngine; using UnityEngine.InputSystem;

public class PlayerMovement : MonoBehaviour { [Header("Player Stats")] [SerializeField] private float runSpeed;

 [SerializeField] private float climbSpeed;

 [SerializeField] private float jumpAmount;

 public bool isLadder;
 public bool isClimbing;

 [Header("Player Specifications")]
 [SerializeField] private Transform groundCheck;

 [SerializeField] private LayerMask groundLayer;

 private float horizontal;
 private float vertical;
 private Rigidbody2D rb;
 private BoxCollider2D playerCollider;

 private void Start()
 {
     rb = GetComponent<Rigidbody2D>();
     playerCollider = GetComponent<BoxCollider2D>();
 }

 private void Update()
 {
     rb.velocity = new Vector2(horizontal * runSpeed, rb.velocity.y);
     FlipPlayer();

     if (isLadder && Mathf.Abs(vertical) > 0f)
     {
         isClimbing = true;
     }
 }

 private void FixedUpdate()
 {
     if (isClimbing)
     {
         rb.gravityScale = 0f;
         rb.velocity = new Vector2(rb.velocity.x, vertical * climbSpeed);
     }
     else
     {
         rb.gravityScale = 10f;
     }
 }

 public void Move(InputAction.CallbackContext context)
 {
     horizontal = context.ReadValue<Vector2>().x;
     vertical = context.ReadValue<Vector2>().y;
 }

 public void Jump(InputAction.CallbackContext context)
 {
     if (context.performed && IsGrounded())
     {
         rb.velocity = new Vector2(rb.velocity.x, jumpAmount);
     }

     if (context.canceled && rb.velocity.y > 0f)
     {
         rb.velocity = new Vector2(rb.velocity.x, rb.velocity.y * 0.5f);
     }
 }

 private bool IsGrounded()
 {
     return Physics2D.OverlapCircle(groundCheck.position, 0.2f, groundLayer);
 }

 private void FlipPlayer()
 {
     bool playerHasHorizontalSpeed = Mathf.Abs(rb.velocity.x) > Mathf.Epsilon;

     if (playerHasHorizontalSpeed)
     {
         transform.localScale = new Vector2(Mathf.Sign(rb.velocity.x), 1f);
     }
 }

 private void OnTriggerEnter2D(Collider2D collision)
 {
     if (collision.CompareTag("Ladder"))
     {
         isLadder = true;
     }
 }

 private void OnTriggerExit2D(Collider2D collision)
 {
     if (collision.CompareTag("Ladder"))
     {
         isLadder = false;
         isClimbing = false;
     }
 }

}