Express nodemail not sending the email in production

Question

I have the following config in my code:

let transporter = nodemailer.createTransport({
    service: 'gmail',
    auth: {
      user: 'user@gmail.com
      pass: 'passwrord'
    }
  })

It works on my localhost but not in production - cpanel a2hosting.

This Nodemailer with Gmail and NodeJS doesn't work for me.