当我按下“跳跃”键时，我的玩家并不总是跳起来.按钮

在我的2D Unity项目中，我的玩家在按下"jump"按钮时并不总是跳跃。他在落地的那一刻不会跳，但在"落地"一秒钟后，他又可以跳了。这是什么问题呢?

using UnityEngine;
    using System.Collections;
    using UnityEngine.UI;
    public class player : MonoBehaviour {
        private static player instance;
        public static player Instance
        {
            get
            {
                if (instance == null)
                {
                    instance = GameObject.FindObjectOfType<player>();
                }
                return instance;
            }
        }

        private Animator myAnimator;
        [SerializeField]
        public static float movementSpeed;
        private bool facingRight = true;
        [SerializeField]
        private Transform[] groundPoints;
        [SerializeField]
        private float groundRadius;
        [SerializeField]
        private LayerMask whatIsGround;
        [SerializeField]
        private bool airControl;
        [SerializeField]
        private float jumpForce;
        public bool canMove;
        public AudioClip jump001;
        public AudioClip jump002;
        private float direction;
        private bool move;
        private float btnHorizontal;
        public Rigidbody2D MyRigidbody { get; set; }
        public bool Attack { get; set; }
        public bool Jump { get; set; }
        public bool OnGround { get; set; }


        // Use this for initialization
        void Start() {
            facingRight = true;
            MyRigidbody = GetComponent<Rigidbody2D>();
            myAnimator = GetComponent<Animator>();


        }
       void Update()
       {
            HandleInput();
        }
        // Update is called once per frame
        void FixedUpdate()
        {
            OnGround = IsGrounded();
            float horizontal = Input.GetAxis("Horizontal");
            if (move)
            {
                this.btnHorizontal = Mathf.Lerp(btnHorizontal, direction, Time.deltaTime * 5);
                HandleMovement(btnHorizontal);
                Flip(direction);
            }
            else
            {
                HandleMovement(horizontal);
                Flip(horizontal);
            }
            if (!canMove)
            {
                GetComponent<Rigidbody2D>().velocity = new Vector2(0, GetComponent<Rigidbody2D>().velocity.y);
                myAnimator.SetFloat("speed", 0);
                return;
            }


            HandleLayers();
        }

        private void HandleMovement(float horizontal)
        {
            if (MyRigidbody.velocity.y < 0)
            {
                myAnimator.SetBool("land", true);
            }
            if (!Attack && (OnGround || airControl))
            {
                MyRigidbody.velocity = new Vector2(horizontal * movementSpeed, MyRigidbody.velocity.y);
            }
            if (Jump && MyRigidbody.velocity.y == 0)
            {
                SoundManager.instance.RandomizeSfx(jump001, jump002);
                MyRigidbody.AddForce(new Vector2(0, jumpForce));
            }
            myAnimator.SetFloat("speed", Mathf.Abs(horizontal));
        }

        private void HandleInput()
        {
            if (canMove)
            {
                //Input.GetKeyDown(KeyCode.Space) || Input.GetKeyDown(KeyCode.UpArrow) || Input.GetKeyDown(KeyCode.W) ||
                if (Input.GetButtonDown("Jump"))
                {
                    myAnimator.SetTrigger("jump");
                }
                if (Input.GetKeyDown(KeyCode.Z) || Input.GetButton("Fight") && OnGround && !Jump)
                {
                    myAnimator.SetTrigger("attack");
                }
            }
        }
        private void Flip(float horizontal)
        {
            if (horizontal > 0 && !facingRight || horizontal < 0 && facingRight && canMove)
            {
                facingRight = !facingRight;
                Vector3 theScale = transform.localScale;
                theScale.x *= -1;
                transform.localScale = theScale;
            }
        }

        private bool IsGrounded()
        {
            {
            }
            if (MyRigidbody.velocity.y <= 0)
            {
                foreach (Transform point in groundPoints)
                {
                    Collider2D[] colliders = Physics2D.OverlapCircleAll(point.position, groundRadius, whatIsGround);
                    for (int i = 0; i < colliders.Length; i++)
                    {
                        if (colliders[i].gameObject != gameObject)
                        {
                            return true;
                        }
                    }
                }
            }
            return false;
        }
        private void HandleLayers()
        {
            if (!OnGround)
            {
                myAnimator.SetLayerWeight(1, 1);
            }
            else
            {
                myAnimator.SetLayerWeight(1, 0);
            }
        }
        //TouchKnappar
        public void BtnJump()
        {
            if (canMove)
            {

                myAnimator.SetTrigger("jump");
                Jump = true;
            }
        }
        public void BtnAttack()
        {
                myAnimator.SetTrigger("attack");
                Attack = true;
        }
        public void BtnMove(float direction)
        {
                this.direction = direction;
                this.move = true;
        }
        public void BtnStopMove()
        {
                this.direction = 0;
                this.btnHorizontal = 0;
                this.move = false;
        }
        public void BtnStopJump()
        {
                Jump = false;

    }

    }