Help with pause menu?

I am having some trouble when implementing a pause menu. Specifically it won't let me press the "resume" or "quit" button. I was hoping someone could help me with this. The specific code for the pause script is as follows:

 using System;
 using UnityEngine;
 using UnityEngine.SceneManagement;
  
 public class PauseGame : MonoBehaviour {
 
     public GameObject playUI;
     public GameObject pauseUI;
 
      bool paused = false;
      public string pauseButton;
  
      void Update()
      {
          if(Input.GetKey(pauseButton))
              pause();
      }
 
      public void pause() {
          pauseUI.SetActive(true);
          playUI.SetActive(false);
          Time.timeScale = 0f;
          paused = true;
      }
 
      public void resume() {
          pauseUI.SetActive(false);
          playUI.SetActive(true);
          Time.timeScale = 1f;
          paused = false;   
      }
  }

I have double-checked that the buttons in the menu refer to the appropriate classes. Any help would be much appreciated.