Email send through nodemailer goes into spam for gmail

I am sending email through nodemailer it goes into inbox of gmail if i run from local server but goes into spam of gmail if i run script from microsoft azure server. following is my script

var nodemailer = require('nodemailer');
var EmailTemplates = require('swig-email-templates');
var smtpConfig =  {
        service: 'smtp.office365.com',
        host: 'smtp.office365.com',
        port: 587,
        starttls: {
            enable: true
        },
        secureConnection: true,
        auth: {
            user: 'xxxxx@yyyy.com',
            pass: 'zzzzzz'
        }
    }

var templates = new EmailTemplates();  
var transporter = nodemailer.createTransport(smtpConfig);   

var context = {
  username:'Rajesh',
  email:'xxxxx@gmail.com',
  link : 'www.google.co.in'
};

templates.render('activate_email.html', context, function(err, html,text, subject) {    

  transporter.sendMail({
    from: '"Product Name👥" <no-reply@xxxxx.com>', // sender address
    to: 'xxxx@gmail.com',
      subject: 'Account activation',
      html: html,
      text:text    
  });    
});

The truth is there is no simple one line solutions for your problem :) There are numerous reasons why this can happen, and here are some of them:

• Your host is marked as a spam - this happens if you have not verified your e-mail or you are sending too much e-mails from the same host. Shared hosting is commonly marked as such, and therefore mail server will regularly mark them as a spam

• Your from field is different than the one you're allowed to use - as I see you're using smtp, there are strict rules for the mail you can send. Of course you can always send e-mail from mark@facebook.com, but since your SMTP's host is not facebook.com, your e-mail will pretty sure marked as spam

• You can sign your e-mail in many various mails, assuring the servers that this e-mail is send from you and it has proper signature. Check online for the ways to do so.

• While developing you have sent numerous alike e-mails - sending the very same "test" e-mail is a common reason for your e-mails to get blacklisted

• There are emojis in your subject - that is not a 100% reason, but servers are often marking such e-mails as spams, especially in other fields (like from)

Unfortunately as I said there is no one real reason, there could be many of them. I hope this helps at least a little :)