Example create issue is returning "Internal Server Error"

[Tamis]

The only difference is that I'm using a password/username for authentification:

var hostname = 'http://redmine:3000';
var config = {
  username:"admin",
  password:"adminadmin"
};
var redmine = new Redmine(hostname, config);
var issue = {
  "issue": {
    "project_id": 1,
    "subject": 'Redmine REST API by Node.js',
    "assigned_to_id": 5,
    "notes": "automative update redmine notes by node js",
    "priority_id": 4
  }
};
redmine.create_issue(issue, function(err, data) {
  if (err) throw err;

  console.log(data);
});

This results in:

{"ErrorCode":500,"Message":"Internal Server Error ","Detail":{"status":500,"error":"Internal Server Error"}}

Not sure why this happens? Using docker container version of redmine. Any clue?