input .lzma too short

Hi everyone, I'm using the Unity Serializer pack and I tried finding help on the offical website but I couldn't find anything. At the moment I want my game to auto-save on exit and auto-load opon starting the game, but I get this really annoying error and I was hoping someone would be able to help me with it.

here is the error:

 Exception: input .lzma is too short
 SevenZipRadical.Compression.LZMA.SevenZipRadicalHelper.Decompress (System.Byte[] inputBytes, ICodeProgress progress) (at Assets/Plugins/whydoidoit.com/7zip/Compress/SevenZipHelper.cs:178)
 CompressionHelper.Decompress (System.String data, ICodeProgress progress) (at Assets/Plugins/whydoidoit.com/7zip/Compress/SevenZipHelper.cs:96)
 LevelSerializer.LoadSavedLevel (System.String data) (at Assets/Plugins/whydoidoit.com/Serialization/LevelSerializer.cs:842)
 CoinSaving.Start () (at Assets/UnitySerializer/Scripts/CoinSaving.js:11)

Here is my code:

 #pragma strict
 var Hasitstarted : int = 0;
 var levelData = PlayerPrefs.GetString("_PAUSE_GAME_","");
 
 function Start () {
     
     Hasitstarted = PlayerPrefs.GetInt("Playedbefore");
     
     if (Hasitstarted == 1)
     {
         LevelSerializer.LoadSavedLevel(levelData);
         Debug.Log("Loaded");
     }
 }
 
 function Update () {
 
     if (Input.GetKeyDown(KeyCode.Escape)) {
         PlayerPrefs.SetString("_PAUSE_GAME_", LevelSerializer.SerializeLevel());
         Hasitstarted = 1;
         
         PlayerPrefs.SetInt("Playedbefore", Hasitstarted);
         Debug.Log("Saved");
     }
 
 }