Not returning student data, don't know why

var students = [ 
  { 
   name: 'Dave',
    track: 'Front End Development',
    achievements: 158,
    points: 14730
  },
  {
    name: 'Jody',
    track: 'iOS Development with Swift',
    achievements: 175,
    points: 16375
  },
  {
    name: 'John',
    track: 'PHP Development',
    achievements: 55,
    points: 2025
  },
  {
    name: 'John',
    track: 'Learn WordPress',
    achievements: 40,
    points: 1950
  },
  {
    name: 'Trish',
    track: 'Rails Development',
    achievements: 5,
    points: 350
  }
];

var html;
var student;
var input;

// print message within output div
function print(message) {
  var outputDiv = document.getElementById('output');
  outputDiv.innerHTML = message;
}

// return student report as ordered list
function getReport(student) {
    var report = '<h2>Student: ' + student.name + '</h2>';
    report += '<ol><li>Track: ' + student.track + '</li>';
    report += '<li>Points: ' + student.points + '</li>';
    report += '<li>Achievements: ' + student.achievements + '</li></ol>';
    return report;
}

// prompt user for student name
while (true) {
  input = prompt('Enter a students name, or type quit to exit.');
// break loop if user inputs quit
    if (input === null || input.toLowerCase() === 'quit') {
      break;
    }
    for ( var i = 0; i < students.length; i += 1 ) {
    student = students[i];
    if ( student.name === input ) {
      html += getReport(student);
      print(html);
    }
  }
}