Unity game object keeps switching from being an object and "null"

SOLVED - 2 copies of the script in unity

I'm working on UI that gets information from a web socket. I have run into a problem where code_object (and code_text) keeps switching from being assigned and null.

(it also causes an error:

UnassignedReferenceException: The variable code_object of WsClient has not been assigned. You probably need to assign the code_object variable of the WsClient script in the inspector. UnityEngine.GameObject.GetComponent[T] () (at <05041d4f5ec242309356a6b3b04452e6>:0) WsClient.Start () (at Assets/scripts/WsClient.cs:20)

because I try to use it while being "null")

I have no idea what could cause the problem, I may have made a stupid but I have no clue.

Debug output debug code

private void Update()
    {if (code_object != null) { Debug.Log("not null"); }
     if (code_object == null) { Debug.Log("null"); }
    }

All code:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using WebSocketSharp;
using TMPro;

public class WsClient : MonoBehaviour
{
    public string code;
    public string message;
    public GameObject code_object;
    TextMeshProUGUI code_text;
    private WebSocket ws;

    private void Start()
    {
        ws = new WebSocket("ws://localhost:8080");
        ws.OnMessage += OnMessage;
        ws.Connect();
        code_text = code_object.GetComponent<TextMeshProUGUI>();
        Debug.Log("code text =" + code_text);
        Debug.Log("code object =" + code_object);
    }

    private void OnMessage(object sender, MessageEventArgs e)
    {
        Debug.Log("Message Received from " + ((WebSocket)sender).Url + ", Data : " + e.Data);

        if (e.Data.Contains("Your code is:"))
        {
            Debug.Log("Code contains 'Your code is:'");
            code = e.Data.Substring("Your code is:".Length);
            Debug.Log(code);
            //code_text = code_object.GetComponent<TextMeshProUGUI>();
            Debug.Log("code text =" + code_text);
            Debug.Log("test");
            Debug.Log("code object =" + code_object);
            Debug.Log("test2");
            if (code_text != null && code != null)
            {
                Debug.Log("'code_text != null && code != null' is true");
                Debug.Log(code);
                code_text.text = code;
            }
           
        }
        else
        {Debug.Log("Code contains 'Your code is:'");
            Debug.Log("Code does not contain 'Your code is:'");
        }
    }
    private void Update()
    {if (code_object != null) { Debug.Log("not null"); }
     if (code_object == null) { Debug.Log("null"); }

        //Debug.Log("code object =" + code_object);
        //Debug.Log(code);
        /*if (code_text != null && code != null)
        {
            Debug.Log("'code_text != null && code != null' is true");
            code_text.text = code;
        }*/
    }
    public void startserver()
    {
        if (ws != null)
        {
            ws.Send("CL");
        }
    }
}

I tried to update the UI but it seems that the error results in nothing happening