OnMouseOver not registering collisions

I’m working on a UI-heavy game and I’d like to add sound effects for when the player mouses over a UI button (using TMP, if that matters). I’ve tried OnMouseOver and its siblings OnMouseEnter and OnMouseStay, I’ve tried with and without 2D Box Colliders, but so far nothing I’ve tried seems to register that the mouse is over the button: i.e. nothing happens. If a collision or Raycast hit were registered, all that I’m asking right now is for it to run the line Debug.Log("Collision detected");

I know that Unity is able to register hits on the UI element I’m testing on, because mousing over it engages the Sprite Swap function that’s part of the Button component, which it would not do if it were not accepting Raycast hits.

I’m sure there’s some very simple solution to this, like a check-box I haven’t ticked, but I could really use some help here.

Many thanks!

using UnityEngine.UI;
using UnityEngine.EventSystems;
using UnityEngine;

public class Test : MonoBehaviour, IPointerEnterHandler
{
    public void OnPointerEnter(PointerEventData eventData)
    {
    Debug.Log("Mouse detected");
    }
}

using UnityEngine.EventSystems;
using UnityEngine.UI;