can't change float value from OnTriggerEnter

when i go in collider Debug shows the text but time is not added :stuck_out_tongue:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
public class LevelTimer : MonoBehaviour {
public Text text;
public float timeLeft = 30.0f;
     void OnTriggerEnter(Collider other) {
    timeLeft += 10f;
     void Update()
         timeLeft -= Time.deltaTime;
		 text.text = timeLeft.ToString("0");
         if(timeLeft < 0)

Is the time changing on the script just not visually in game?? If so try removing the “0” in .ToString();