Unity2D跳跃/下落动画异常问题求助

我正在跟随YouTuber Antarsoft的2D移动与动画教程，完成跳跃动画环节时，完全按照教程操作后，跳跃状态下动画播放异常。尝试关闭动画循环，但仅导致动画无法播放，未找到其他有效解决方案，同类帖子的解决方法也与我的代码不匹配。

问题表现 #

跳跃时动画播放不符合预期（原视频展示异常状态）

PlayerMovement脚本代码 #

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class PlayerMovement : MonoBehaviour
{
    const float groundCheckRadius = 0.2f;
    const float overheadCheckRadius = 0.2f;
    [SerializeField] float speed = 1;
    [SerializeField] float jumpPower = 65;

    Rigidbody2D rb;
    Animator animator;
    [SerializeField]Collider2D standingCollider;

    [SerializeField] Transform groundCheckCollider;
    [SerializeField] Transform overheadCheckCollider;
    [SerializeField] LayerMask groundLayer; 

    float horizontalValue;
    float runSpeedModifier = 2f;
    float crouchSpeedModifier = 0.5f;
    [SerializeField] bool isGrounded;
    bool jump;
    [SerializeField] bool crouchPressed;
    bool isRunning;
    bool facingRight = true;

    private void Awake()
    {
        rb = GetComponent<Rigidbody2D>();
        animator = GetComponent<Animator>();
    }

    // Update is called once per frame
    void Update()
    {

        //Set they yVelocity in the animator
        animator.SetFloat("yVelocity", rb.velocity.y);

        horizontalValue = Input.GetAxisRaw("Horizontal");

        if (Input.GetKeyDown(KeyCode.LeftShift))
        isRunning = true;
        if (Input.GetKeyUp(KeyCode.LeftShift))
        isRunning = false;

        if (Input.GetButtonDown("Jump"))
        {
            jump = true;
            animator.SetBool("Jump", true);
        }
        else if(Input.GetButtonUp("Jump"))
        jump = false;

        if (Input.GetKeyDown(KeyCode.LeftShift))
        isRunning = true;
        if (Input.GetKeyUp(KeyCode.LeftShift))
        isRunning = false;

        if (Input.GetButtonDown("Crouch"))
        crouchPressed = true;
        else if (Input.GetButtonUp("Crouch"))
        crouchPressed = false;



    }

    void FixedUpdate()
    {
        GroundCheck();
        Move(horizontalValue, jump, crouchPressed);
    }

    void GroundCheck()
    {
        isGrounded = false;

        Collider2D[] colliders = Physics2D.OverlapCircleAll(groundCheckCollider.position, groundCheckRadius, groundLayer);
        if (colliders.Length > 0)   
        isGrounded = true;

        animator.SetBool("Jump", !isGrounded);
    }

    void Move(float dir,bool jumpFlag,bool crouchFlag)
    {
        #region jump and crouch

        if (!crouchFlag)
        {
            if (Physics2D.OverlapCircle(overheadCheckCollider.position,overheadCheckRadius,groundLayer))
            crouchFlag = true;

        }

        if (isGrounded)
        {
            standingCollider.enabled = !crouchFlag;



            //If the player is grounded press space to jump
            if (jumpFlag)
            {
                //isGrounded = false;
                jumpFlag = false;
                //Add jump force    
                rb.AddForce(new Vector2(0f, jumpPower));
            }

        }

        animator.SetBool("Crouch", crouchFlag);

        #endregion
        #region move and run
        //Set value of x using dir and speed
        float xVal = dir * speed * 100 * Time.fixedDeltaTime;
        if (isRunning)
        xVal *= runSpeedModifier;

        if (crouchFlag)
        xVal *= crouchSpeedModifier;
        //Create Vec2 for the Velocity
        Vector2 targetVelocity = new Vector2(xVal, rb.velocity.y);
        //Set the players Velocity
        rb.velocity = targetVelocity;

        //If looking right and press left, turn left
        if (facingRight && dir < 0)
        {
            transform.localScale = new Vector3(transform.localScale.x * -1, transform.localScale.y, transform.localScale.z);
            facingRight = false;
        }
        //If looking left and press right, turn to the right
        else if (!facingRight && dir > 0)
        {
            transform.localScale = new Vector3(transform.localScale.x * -1, transform.localScale.y, transform.localScale.z);
            facingRight = true;
        }

        Debug.Log(rb.velocity.x);
        animator.SetFloat("xVelocity", Mathf.Abs(rb.velocity.x));
        #endregion
    }
}

内容的提问来源于stack exchange，提问作者Mohammed Hussain