im having problem with jumping i want to only jump once becuase now player can go high as much as can, i want when player jumps on the ground he cant jump until he touches ground again

[Maksim12332112]

using UnityEngine;
using UnityEngine.Events;

public class CharacterController2D : MonoBehaviour
{
[SerializeField] private float m_JumpForce = 400f; // Amount of force added when the player jumps.
[Range(0, 1)] [SerializeField] private float m_CrouchSpeed = .4f; // Amount of maxSpeed applied to crouching movement. 1 = 100%
[Range(0, .3f)] [SerializeField] private float m_MovementSmoothing = .05f; // How much to smooth out the movement
[SerializeField] private bool m_AirControl = true; // Whether or not a player can steer while jumping;
[SerializeField] private LayerMask m_WhatIsGround; // A mask determining what is ground to the character
[SerializeField] private Transform m_GroundCheck; // A position marking where to check if the player is grounded.
[SerializeField] private Transform m_CeilingCheck; // A position marking where to check for ceilings
[SerializeField] private Collider2D m_CrouchDisableCollider; // A collider that will be disabled when crouching

const float k_GroundedRadius = 2f;
private bool m_Grounded;            // Whether or not the player is grounded.
const float k_CeilingRadius = .2f; // Radius of the overlap circle to determine if the player can stand up
private Rigidbody2D m_Rigidbody2D;
private bool m_FacingRight = true;  // For determining which way the player is currently facing.
private Vector3 m_Velocity = Vector3.zero;

[Header("Events")]
[Space]

public UnityEvent OnLandEvent;

[System.Serializable]
public class BoolEvent : UnityEvent<bool> { }

public BoolEvent OnCrouchEvent;
private bool m_wasCrouching = false;

private void Awake()
{
	m_Rigidbody2D = GetComponent<Rigidbody2D>();

	if (OnLandEvent == null)
		OnLandEvent = new UnityEvent();

	if (OnCrouchEvent == null)
		OnCrouchEvent = new BoolEvent();
}

private void FixedUpdate()
{
	bool wasGrounded = m_Grounded;
	m_Grounded = false;

	// The player is grounded if a circlecast to the groundcheck position hits anything designated as ground
	// This can be done using layers instead but Sample Assets will not overwrite your project settings.
	Collider2D[] colliders = Physics2D.OverlapCircleAll(m_GroundCheck.position, k_GroundedRadius, m_WhatIsGround);
	for (int i = 0; i < colliders.Length; i++)
	{
		if (colliders*.gameObject != gameObject)*

•   	{*
  

•   		m_Grounded = true;*
  

•   		if (!wasGrounded)*
  

•   			OnLandEvent.Invoke();*
  

•   	}*
  

•   }*
  

• }*
• public void Move(float move, bool crouch, bool jump)*
• {*

•   // If crouching, check to see if the character can stand up*
  

•   if (!crouch)*
  

•   {*
  

•   	// If the character has a ceiling preventing them from standing up, keep them crouching*
  

•   	if (Physics2D.OverlapCircle(m_CeilingCheck.position, k_CeilingRadius, m_WhatIsGround))*
  

•   	{*
  

•   		crouch = true;*
  

•   	}*
  

•   }*
  

•   //only control the player if grounded or airControl is turned on*
  

•   if (m_Grounded || m_AirControl)*
  

•   {*
  

•   	// If crouching*
  

•   	if (crouch)*
  

•   	{*
  

•   		if (!m_wasCrouching)*
  

•   		{*
  

•   			m_wasCrouching = true;*
  

•   			OnCrouchEvent.Invoke(true);*
  

•   		}*
  

•   		// Reduce the speed by the crouchSpeed multiplier*
  

move *= m_CrouchSpeed;

•   		// Disable one of the colliders when crouching*
  

•   		if (m_CrouchDisableCollider != null)*
  

•   			m_CrouchDisableCollider.enabled = false;*
  

•   	} else*
  

•   	{*
  

•   		// Enable the collider when not crouching*
  

•   		if (m_CrouchDisableCollider != null)*
  

•   			m_CrouchDisableCollider.enabled = true;*
  

•   		if (m_wasCrouching)*
  

•   		{*
  

•   			m_wasCrouching = false;*
  

•   			OnCrouchEvent.Invoke(false);*
  

•   		}*
  

•   	}*
  

•   	// Move the character by finding the target velocity*
  

Vector3 targetVelocity = new Vector2(move * 10f, m_Rigidbody2D.velocity.y);

•   	// And then smoothing it out and applying it to the character*
  

•   	m_Rigidbody2D.velocity = Vector3.SmoothDamp(m_Rigidbody2D.velocity, targetVelocity, ref m_Velocity, m_MovementSmoothing);*
  

•   	// If the input is moving the player right and the player is facing left...*
  

•   	if (move > 0 && !m_FacingRight)*
  

•   	{*
  

•   		// ... flip the player.*
  

•   		Flip();*
  

•   	}*
  

•   	// Otherwise if the input is moving the player left and the player is facing right...*
  

•   	else if (move < 0 && m_FacingRight)*
  

•   	{*
  

•   		// ... flip the player.*
  

•   		Flip();*
  

•   	}*
  

•   }*
  

•   // If the player should jump...*
  

•   if (m_Grounded && jump)*
  

•   {*
  

•   	// Add a vertical force to the player.*
  

•   	m_Grounded = true;*
  

•   	m_Rigidbody2D.AddForce(new Vector2(0f, m_JumpForce));*
  

•   }*
  

• }*
• private void Flip()*
• {*

•   // Switch the way the player is labelled as facing.*
  

•   m_FacingRight = !m_FacingRight;*
  

•   // Multiply the player's x local scale by -1.*
  

•   Vector3 theScale = transform.localScale;*
  

_ theScale.x *= -1;_

•   transform.localScale = theScale;*
  

• }*
  }
  And for other one
  using System.Collections;
  using System.Collections.Generic;
  using UnityEngine;
  public class siii : MonoBehaviour
  {
  public CharacterController2D controller;
  public Animator animator;
  public float runSpeed = 40f;
  float horizontalMove = 0f;
  bool jump = false;
  bool crouch = false;
  // Update is called once per frame
  void Update()
  {
  horizontalMove = Input.GetAxisRaw(“Horizontal”) * runSpeed;
  animator.SetFloat(“Speed 0”, Mathf.Abs(horizontalMove));
  if (Input.GetButtonDown(“Jump”))
  {
  jump = true;
  animator.SetBool(“isjumping”, true);
  }
  if (Input.GetButtonDown(“Crouch”))
  {
  crouch = true;
  }
  else if (Input.GetButtonUp(“Crouch”))
  {
  crouch = false;
  }
  }
  public void Onlanding ()
  {
  animator.SetBool(“isjumping”, false);
  jump = false;
  }
  public void OnCrouching (bool isCrouching)
  {
  animator.SetBool(“IsCrouching”, isCrouching);
  }
  void FixedUpdate()
  {
  // Move our character
  controller.Move(horizontalMove * Time.fixedDeltaTime, crouch, jump);
  jump = false;
  }
  }

[HappyPixel27]

Did you make the script yourself? It seems to me that your script is from a unity asset. If so contact the developer about it. If you made it yourself i recommend to see the video Brackeys made on youtube on first person controllers. You can find the link here: FIRST PERSON MOVEMENT in Unity - FPS Controller - YouTube