WRONG implementation: RabbitMQ client closes the connection after 2 secs

receive.js

#!/usr/bin/env node

'use strict';

const amqp = require('amqplib');

const sleep = async (ms) => new Promise(resolve => setTimeout(resolve, ms));

(async () => {
  const conn = await amqp.connect('amqp://localhost:9520');
  process.once('SIGINT', () => conn.close());
  const ch = await conn.createChannel();

  await ch.assertQueue('hello', { durable: false });
  await ch.prefetch(1);

  await ch.consume('hello', async (msg) => {
    console.log(" [x] Received '%s'", msg.content.toString());
    await sleep(500);
    ch.ack(msg);
  });

  setTimeout(()=>{
    ch.close();
    console.log(' [*] Finished');
  }, 2000);

})();