2d Jumping Problem

I am having a problem trying to fix a jump to a single jump with a double jump as a powerup. I have this code but I am constantly jumping.

How can I fix this and add a double jump?

Character3D Controller

 public class CharacterController2D : MonoBehaviour
 {
 
     [SerializeField] private float m_JumpForce = 400f;                            
     [Range(0, .3f)] [SerializeField] private float m_MovementSmoothing = .05f;    
     [SerializeField] private bool m_AirControl = false;                            
     [SerializeField] private LayerMask m_WhatIsGround;                            
     [SerializeField] private Transform m_GroundCheck;                            
     [SerializeField] private Transform m_CeilingCheck;                            
     [SerializeField] private Collider2D m_CrouchDisableCollider;                
 
     const float k_GroundedRadius = .2f; 
     private bool m_Grounded;            
     const float k_CeilingRadius = .2f; 
     private Rigidbody2D m_Rigidbody2D;
     private bool m_FacingRight = true;  
     private Vector3 m_Velocity = Vector3.zero;
 
     [Header("Events")]
     [Space]
 
     public UnityEvent OnLandEvent;
 
     [System.Serializable]
     public class BoolEvent : UnityEvent<bool> { }
 
 
     private void Awake()
     {
         m_Rigidbody2D = GetComponent<Rigidbody2D>();
 
         if (OnLandEvent == null)
             OnLandEvent = new UnityEvent();
     }
 
     private void FixedUpdate()
     {
         bool wasGrounded = m_Grounded;
         m_Grounded = false;
 
         Collider2D[] colliders = Physics2D.OverlapCircleAll(m_GroundCheck.position, k_GroundedRadius, m_WhatIsGround);
         for (int i = 0; i < colliders.Length; i++)
         {
             if (colliders[i].gameObject != gameObject)
             {
                 m_Grounded = true;
                 if (!wasGrounded)
                     OnLandEvent.Invoke();
             }
         }
     }
 
 
     public void Move(float move, bool jump)
     {
             Vector3 targetVelocity = new Vector2(move * 10f, m_Rigidbody2D.velocity.y);
             m_Rigidbody2D.velocity = Vector3.SmoothDamp(m_Rigidbody2D.velocity, targetVelocity, ref m_Velocity, m_MovementSmoothing);
 
             if (move > 0 && !m_FacingRight)
             {
                 Flip();
             } else if (move < 0 && m_FacingRight)
             {
                 Flip();
             }
         
 
             if (m_Grounded && jump)
             {
                 m_Grounded = false;
                 m_Rigidbody2D.AddForce(new Vector2(0f, m_JumpForce));
             }
         }
 
 
     private void Flip()
     {
         m_FacingRight = !m_FacingRight;
         transform.Rotate(0f, 180f, 0f);
     }
 }

And the Player Movement

     public CharacterController2D controller;
     public Animator animator;
 
     public float runSpeed = 40f;
 
     float horizontalMove = 0f;
     bool jump = false;
 
 
     // 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);
         }    
     }
 
     public void OnLanding ()
     {
     //    animator.SetBool("IsJumping", false);
     }
 
 
 
     void FixedUpdate ()
     {
         // Move our character
         controller.Move(horizontalMove * Time.fixedDeltaTime, false, jump);
         jump = false;
     }
 }