Nodemailer with Mailgun

I am trying to send out emails when a user signs up to my site. I decided on Nodemailer and MailGun and have come to realize there is not many tutorials or good docs on them working together. Seems to be a similar issue for the rest of the services like MailGun. Below is my code for an attempt at getting it to work. I watched a tutorial on getting it to work but cant seem to figure it out. I think the code is right but maybe the auth is wrong? Or I could just be off on both. I am using cloud9.io for my dev environment so maybe that is the issue? Or that my domain is not verified yet?

Route:

app.post('/signup',
    setRedirect({auth: '/dashboard', success: '/dashboard', failure: '/signup'}),
    isUnauthenticated,
    registrations.postSignup,
    (req, res) =>{
      const output = `
        <h1>Your email is: ${req.body.email}</h1>
         `;

      // create reusable transporter object using the default SMTP transport
      let transporter = nodemailer.createTransport({
        host: 'postmaster@MYSUBDOMAIN',
        port: 587,
        secure: false, // true for 465, false for other ports
        auth: {
            user: 'postmaster@MYSUBDOMAIN', // generated ethereal user
            pass: 'MYPASSWORD'  // generated ethereal password
        },
        tls:{
          rejectUnauthorized:false
        }
      });

      // setup email data with unicode symbols
      let mailOptions = {
          from: '"Nodemailer Contact"<your@email.com>', // sender address
          to: '`${req.body.email}`', // list of receivers
          subject: 'Node Contact Request', // Subject line
          text: 'Hello world?', // plain text body
          html: output // html body
      };

      // send mail with defined transport object
      transporter.sendMail(mailOptions, (error, info) => {
          if (error) {
              return console.log(error);
          }
          console.log('Message sent: %s', info.messageId);   
          console.log('Preview URL: %s', nodemailer.getTestMessageUrl(info));

          // render view here and pass in data/message
      });
    });

Then the domain information from mailgun.com:

State
Unverified
IP Address
IPASSIGNED Manage IPs
SMTP Hostname
smtp.mailgun.org
Default SMTP Login
postmaster@MYSUBDOMAIN
API Base URL
https://api.mailgun.net/v3/MYSUBDOMAIN
Default Password
MYPASSWORD SMTP credentials
API Key
MYKEY