Basic 2D player controller with long jump for Unity

BasicPlayerMove2D.cs

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

public class PlayerMove : MonoBehaviour
{
    private Rigidbody2D rb;
    private float moveInput;

    public float speed;
    public float jumpForce;
    public float jumpTime;

    private bool isJumping;
    private float jumpTimeCounter;

    private bool isTouching;
    private Collider2D coll;

    private void Start()
    {
        rb = GetComponent<Rigidbody2D>();
        coll = GetComponent<Collider2D>();
    }

    private void FixedUpdate()
    {
        moveInput = Input.GetAxisRaw("Horizontal");
        rb.velocity = new Vector2(moveInput * speed, rb.velocity.y);
    }

    private void Update()
    {
        if (Physics2D.IsTouchingLayers(coll) && Input.GetKeyDown(KeyCode.Space))
        {
            isJumping = true;
            jumpTimeCounter = jumpTime;
            rb.velocity = Vector2.up * jumpForce;
        }

        if (Input.GetKey(KeyCode.Space) && isJumping == true)
        {
            if (jumpTimeCounter > 0)
            {
                rb.velocity = Vector2.up * jumpForce;
                jumpTimeCounter -= Time.deltaTime;
            } else
            {
                isJumping = false;
            }
        }

        if (Input.GetKeyUp(KeyCode.Space))
        {
            isJumping = false;
        }
    }
}