Why data will be overwrite in the file

This is working fine but i realise that the file will be overwrite every time a new game is play which is not i want. I want to maintain the data. Instead of overwrite the data, i want to add on to the data. Any thing bother me is regarding, how we know this file is belong to which players. Is it any possible way i can solve this issues? Like this data in this file is the record play by may.. Please help!!! :((

 using UnityEngine;
 using System.Collections;
 using System;
 using System.Text;
 using System.IO;
 
 public class Monitor : MonoBehaviour {
     
     String path;
     String fileName;
     String playerName;
     int id =1;
     // Use this for initialization
     void Start () 
     {
         fileName = "/Monitoring.txt";
         playerName = playerControl.playerName;
         print(gameControl.previousWord1);
     }
     
     // Update is called once per frame
     void Update () 
     {
         //string messageToAccess = gameControl.previousWord1;
         path = Application.dataPath + fileName;
         
         using(FileStream fs = File.Create(path))
         {
             AddText(fs, "PlayerName: " + playerName);
             AddText(fs, "\r\n================================");
             AddText(fs, "\r\n" + id);
             for(int j = 0; j < gameControl.radical00Store.length; j++)
             {
                 AddText(fs, "\t" + gameControl.radical00Store[j]);
                 AddText(fs, "\t" + gameControl.radical0Store[j]);
                 AddText(fs, "\t" + gameControl.previousWord1[j]);
             }
             AddText(fs, "\t" + gameControl.wrongMatch + "\n");
         }
         id++;
         
          //Open the stream and read it back.
         using (FileStream fs = File.OpenRead(path))
         {
             byte[] b = new byte[1024];
             UTF8Encoding temp = new UTF8Encoding(true);
             while (fs.Read(b,0,b.Length) > 0)
             {
                 Console.WriteLine(temp.GetString(b));
             }
         }
     }
     
     
     private static void AddText(FileStream fs, string value)
     {
         byte[] info = new UTF8Encoding(true).GetBytes(value);
         fs.Write(info, 0, info.Length);
     }
     
 }