Why does mysql write access_denied_error after installation on hosting, installed everything according to the documentation?

Question

MySQL

Good night. I'm trying to start on the host, documentation
Project on node.js, everything is ok, everything starts, except mysql, I connect via socketPath, googled the problem, they advised me to put socketPath in the port, it didn't work ..
I threw a ticket in those. support, I’m waiting, maybe one of you guys has come across, I’ll be most grateful for the help, because. worth development
Here is my class, I take data from dotenv

const { mysql,dotenv,initializeDotenv,util } = require('./packages')

class Mysql {

  constructor(host,user,password,database,socket) {

    this.connection
    this.host = host
    this.user = user
    this.password = password
    this.database = database
    this.socket = socket

    if(socket) {
      this.connection = mysql.createPool({
           socketPath: this.socket,
           port: 3306,
           user: this.user,
           password: this.password,
           database: this.database
      })
    }

    else {
      this.connection = mysql.createPool({
           host: this.host,
           port: 3306,
           user: this.user,
           password: this.password,
           database: this.database
      });
    }

    return this.connection
  }

}

const { HOST,USER,PASSWORD,DATABASE,SOCKET } = process.env;

const pool = new Mysql(HOST,USER,PASSWORD,DATABASE,SOCKET)

pool.getConnection((err, connection) => {
  if (err) {
    console.error(err.code)
  }
  if (connection) connection.release()
})

pool.query = util.promisify(pool.query)

module.exports = { Mysql,pool }

.env

#Project mode
NODE_ENV=production

#App port
PORT=51583

#Mysql

HOST=localhost

USER=user

PASSWORD=password

DATABASE=db

SOCKET=/var/run/mysqld/mysqld.sock

#Bcrypt

COMPLEXITY=10

#Secret for sessions

SECRET=$$999$$

Answer 1

does mysql -u user -p password -s /var/run/mysqld/mysqld.sock
work?