WebSocket connection to 'wss://******/socket.io/?EIO=4&transport=websocket&sid=T2Sf_4oNIisxKLwsAAAK' failed

I'm making a WebSocket connection with socket.io and when I log in, I get this error:

WebSocket connection to 'wss://******/socket.io/?EIO=4&transport=websocket&sid=T2Sf_4oNIisxKLwsAAAK' failed:websocket.js:54

But then the connection is established, although I'm not sure if it's done correctly. It hasn't caused me any issues, but that error always appears first when starting, and then everything works fine.
But the thing is, once I'm logged in, everything seems to work just fine after the error. It's just that this error pops up at the beginning, and I want to make sure it won't cause any issues once it's in production. I'd really appreciate any help you can provide. Thanks a bunch in advance!

This is my server code with express:

const http = require('http');
const server = http.createServer(app);

const { Server } = require('socket.io')
const io = new Server(server)

This is my client code:

       var socket = io.(Config.getHost());
       socket.emit('connection', {
           console.log('*******');
       });
   
       socket.on('disconnect', function() {
           console.log('*******');
       });

I don't know if this would help, but I have no error in my console. In my own case, my client is an angular project. So I established my connection on server as follow.

const app = require('express')();
const httpServer = require('http').createServer(app);
const cors = require('cors');
const io = require('socket.io')(httpServer, {
cors: {
origin : 'http://localhost:4200',
methods: ["GET", "POST"],  
},
});
const { instrument } = require("@socket.io/admin-ui");
const passport = require('passport');
const bcrypt = require('bcrypt');
const bodyParser = require("body-parser");
const LocalStrategy = require('passport-local').Strategy;
const port = 3000;
const shapes = {}; // Store shapes on the server
const { Pool } = require('pg')
const dotenv = require('dotenv');
dotenv.config();
const session = require('express-session');
const pgSession = require('connect-pg-simple')(session);
app.use(require('express').json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cors({
origin : 'http://localhost:4200',
methods: ["GET", "POST"],
}));
io.on('connection', (socket) => {
const shapeTypes = ['Circle', 'Rect', 'Line', 'Arrow', 'Text'];
shapeTypes.forEach((shapeType) => {
socket.on(`create${shapeType}`, (shapeData) => {
shapes[shapeData.id] = shapeData;
io.emit(`create${shapeType}`, shapeData);
});
socket.on(`update${shapeType}`, (shapeData) => {
shapes[shapeData.id] = shapeData;
io.emit(`update${shapeType}`, shapeData);
});
});
// Handle disconnection
socket.on('disconnect', () => {
console.log('A client disconnected');
});
});
instrument(io, {
auth: false,
mode: "development",
});
httpServer.listen(port, () => console.log(`listening on port ${port}`));

and in my angular, I did just simple connection.

import { io } from 'socket.io-client';
public io = io('http://localhost:3000'); // I initialized this in the constructor

I can do io.emit and io.on

Just to clarify the issue, the problem was resolved by configuring the proxy in the httpd.conf file with the WebSocket protocol using the following settings:

ProxyPass /socket.io ws://127.0.0.1:5001/socket.io connectiontimeout=3000 timeout=3000
ProxyPassReverse /socket.io ws://127.0.0.1:5001/socket.io

This allowed for successful communication between the server and the application.I hope this solution helps somebody else facing a similar issue in the future!