adding/interacting with box collider on a ground plane

Hey y'all,

I'm trying to make a 6-foot circle on the ground around the user that turns red when someone enters the circle.

I added a box collider around the ground plane and set it as a trigger, then added this script that should enable the red circle and disable the green circle when someone enters it:

public class TriggerScript : MonoBehaviour {

    public GameObject redCircle;     public GameObject greenCircle;

    public void OnTriggerEnter(Collider other)     {         redCircle.SetActive(true);         greenCircle.SetActive(false);

    }

    public void OnTriggerExit(Collider other)     {

        redCircle.SetActive(false);         greenCircle.SetActive(true);     }

}

I think the issue is that the box collider is expecting to interact with another GameObject, not a person.

Anyone have any recommendations as to how I should go about this? Thanks!