Problem with isometric movement script

I’m trying to create a movement script for an isometric game, I’ve watched a tutorial for this as I am a beginner in coding and unity, I managed to make the “character” (a box as a placeholder) move around, but did not manage to create a jump script, I get the error "error CS1525: Unexpected symbol `else’ "
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class CharController : MonoBehaviour {

    [SerializeField]

    public float moveSpeed = 4f;

    Vector3 forward, right;

    public bool jump = false;
    public float jumpHeight = 8f, jumpSpeed = 10f;
    Rigidbody rb;

	
	void Start ()
    {
        forward = Camera.main.transform.forward;
        forward.y = 0;
        forward = Vector3.Normalize(forward);
        right = Quaternion.Euler(new Vector3(0, 90, 0)) * forward;
        rb = GetComponent<Rigidbody>();
		
	}
	
	
	void Update ()
    {
        if (Input.GetButtonDown("Jump") && !jump) 
        else 
            Move();
	}

    void Move()
    {
        Vector3 direction = new Vector3(Input.GetAxis("HorizontalKey"), 0, Input.GetAxis("VerticalKey"));
        Vector3 rightMovement = right * moveSpeed * Time.deltaTime * Input.GetAxis("HorizontalKey");
        Vector3 upMovement = forward * moveSpeed * Time.deltaTime * Input.GetAxis("VerticalKey");

        Vector3 heading = Vector3.Normalize(rightMovement + upMovement);

        transform.forward = heading;
        transform.position += rightMovement;
        transform.position += upMovement;
        

    }
    IEnumerator Jump()
    {
        float originalHeight = transform.position.y;

        jump = true;
        yield return null;

        //rb.usegravity - false; // disable gravity so we can move our transform without resistance
        rb.AddForce(Vector3.up * jumpHeight, ForceMode.Impulse);

        //float maxHeight - originalHeight + jumpHeight;

        /*while(transform.position.y < maxHeight)
         * {
         * transform.position += tranform.up * Time.deltaTime * jumpSpeed;
         * yield return null;
         * {
         */
        //rb.useGravity = true;
        
         while (transform.position.y > originalHeight)
           
          {
            transform.position -= transform.up * Time.deltaTime * jumpSpeed;
          yield return null;
            rb.useGravity = true;

            jump = false;

            yield return null;


        }

        

      

    }
}

In your Update method you are missing a semicolon:

if (Input.GetButtonDown("Jump") && !jump) 
         else

if (Input.GetButtonDown("Jump") && !jump);
         else