Uncrouch on realese?

I need to Uncrouch on Key Release “C”

Here is the code:

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

public class Crouch : MonoBehaviour {

private CharacterController m_CharacterController;

private bool m_Crouch = false;

private float m_OriginalHeight;
float speed = 5f;

[SerializeField] private float m_CrouchHeight = 0.5f;

public KeyCode crouchKey = KeyCode.C;

void Start()
{
    m_CharacterController = GetComponent<CharacterController>();
    m_OriginalHeight = m_CharacterController.height;
}
void Update()
{
    if (Input.GetKeyDown(crouchKey))
    {
        m_Crouch = !m_Crouch;

        CheckCrouch();
    }
    else if (Input.GetKeyUp(crouchKey))
    {
        // What do i do here?? 
    }
}

void CheckCrouch() {
    if (m_Crouch == true) {
        m_CharacterController.height = m_CrouchHeight;
}
else {
       m_CharacterController.height = m_OriginalHeight;
}

}
}

void Update()
{
if (Input.GetKeyDown(crouchKey))
m_CharacterController.height = m_CrouchHeight;
else if (Input.GetKeyUp(crouchKey))
m_CharacterController.height = m_OriginalHeight;
}