My character cant move right or left when jumping?

i set up a movement script with animations. The animations work when i go left or right or if i jump. But when jumping if im mid air i cant move left or right. If i right first and then jump it jumps to the right but i cant jump first and THEN move. How do i fix this?

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

public class PlayerMovement : MonoBehaviour
{
    public ImprovedMovement controller;
    float horizontalMove = 0f;
    public float runSpeed = 40f;
    bool Jump = false;
    bool Crouch = false;
    public Animator animator;
    

    // Update is called once per frame
    void Update()
    {
      horizontalMove = Input.GetAxisRaw("Horizontal") * runSpeed;

      animator.SetFloat("speed", 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);
    }

    void FixedUpdate ()
    {
        //movement
        controller.Move(horizontalMove * Time.fixedDeltaTime, Crouch, Jump);
        Jump = false;

        
    }

}