String format not working

Probably something really simple I am missing. But I can’t seem to fix this problem. Do you guys/gals see the problem anywhere?

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

public class TimerScript : MonoBehaviour {
	
	public Text theText;
	private double time = 0;
	private int check = 1;

	public void Update(){
		
		if (check == 0) {
			time += Time.deltaTime;
			theText.text = string.Format("{0:0.0}",time.ToString());
		}
	}

	public void startPressed(){
		check = 0;
		
	}

	public void stopPressed(){
		check = 1;
	
	}
}

Fixed… Changed this

theText.text = string.Format("{0:0.0}",time.ToString());

To

theText.text = time.ToString("0000.00");

Hope can anyone explain why the latter works, but not the former? Thanks