title: Mongoose not saving data with no error
body: <p>I have this code </p>
  
  <pre><code>      User.findOne({ email: req.body.email }, function(err, user) {
          if (user) {
            return res.status(400).json([{ msg: 'The email address you have entered is already associated with another account.' }]);
          }
          user = new User({
            name: req.body.name,
            email: req.body.email,
            password: req.body.password,
            mobile: req.body.mobile
          });
          user.save(function(err) {
            res.json({ token: generateToken(user), user: user });
          });
        });
  </code></pre>
  
  <p>I tried sending a request with postman and I did get a response back with the user object which means there is no err in the save function</p>
  
  <pre><code>{
    "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJleGNlcHRpb25zLnNnIiwic3ViIjoiNTc5NWQ0NzQxYmEzZWQwODE1ZTgzY2NmIiwiaWF0IjoxNDY5NDM3MDQ0LCJleHAiOjE0NzAwNDE4NDR9.2otkcPkJgsXvR8QOHAojDJ5YCxR7Uc2E4ApS77T55F8",
    "user": {
      "__v": 0,
      "created_at": "2016-07-25T08:57:24.612Z",
      "updated_at": "2016-07-25T08:57:24.612Z",
      "name": "Test",
      "email": "Test@hotmail.com",
      "password": "$2a$10$3UmABiDPeo6iHZ.DFbwOO.1ANpUWQmwr86bYbTmRuFedsbDcE0bbC",
      "mobile": 12345,
      "_id": "5795d4741ba3ed0815e83ccf"
    }
  }
  </code></pre>
  
  <p>However there is no entry of this inside my DB. I've check through my database with Robomongo and I'm sure that there is no data. What did I missed out?</p>