Error writting a file

I make a code to write a text file named "SaveEssentials" on a folder named "Save", the problem is, when i run the game and run the script, the folder and the file are created, but there is nothing in the file.

This error shows me up every time when i run the game:

DirectoryNotFoundException: Could not find a part of the path "C:\Users\User\Documents\Unity\RPG\Save\SaveEssentials.txt". System.IO.FileStream..ctor (System.String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, Boolean anonymous, FileOptions options) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.IO/FileStream.cs:292) System.IO.FileStream..ctor (System.String path, FileMode mode, FileAccess access, FileShare share) (wrapper remoting-invoke-with-check) System.IO.FileStream:.ctor (string,System.IO.FileMode,System.IO.FileAccess,System.IO.FileShare) System.IO.StreamWriter..ctor (System.String path, Boolean append, System.Text.Encoding encoding, Int32 bufferSize) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.IO/StreamWriter.cs:124) System.IO.StreamWriter..ctor (System.String path, Boolean append) (wrapper remoting-invoke-with-check) System.IO.StreamWriter:.ctor (string,bool) System.IO.File.CreateText (System.String path) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.IO/File.cs:159) SaveGame..ctor () (at Assets/Scripts/Objects/Game/SaveGame.js:8)

And here is my code:

 #pragma strict
 import System;
 import System.IO;
 
 var folder : String = "Save";
 var fileName : String = "SaveEssentials";
 var extension : String = "txt";
 var crFile = File.CreateText("./" + folder + "/" + fileName + "." + extension);
 var triggered : boolean = false;
 
 function OnTriggerEnter2D(EventCollider: Collider2D) {
         triggered = true;
 }
 
 function OnTriggerExit2D(EventCollider: Collider2D) {
         triggered = false;
 }
 
 function Update () {
     if (triggered == true){
         if (Input.GetKeyDown ("return")){
             if (Directory.Exists("./" + folder)){
                 crFile.WriteLine (GameEssentials.playerName);
                 crFile.WriteLine (GameEssentials.level);
                 crFile.WriteLine (GameEssentials.exp);
             }
             else
              {
                 Directory.CreateDirectory ("./" + folder);
                 crFile.WriteLine (GameEssentials.playerName);
                 crFile.WriteLine (GameEssentials.level);
                 crFile.WriteLine (GameEssentials.exp);
             }
         }
     }
 }

GameEssentials is another script