json data cannot bind to html page in Web Api in Angular page

I'm trying to bind some data that is coming from ms sql database to a single page angular. apparently everything is working fine and I can see the data in json format in network response of the browser but the problem is data cannot bind to ng-repeat tag in html file.

here is my html file

<div class="row">
<h1>Users</h1>
<div class="span10">
    <table class="table table-condenced table-hover">
        <tr>
            <th>User</th>
            <th>user firstname</th>
            <th>user lastname</th>
        </tr>
        <tr ng-repeat="user in users">
            <th>{{user.UserID}}</th>
            <th>{{user.Lastname}}</th>
            <th>{{user.Firstname}}</th>
        </tr>
    </table>
</div>

here is my model

using Newtonsoft.Json;
using Newtonsoft.Json.Serialization;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Http.Formatting;
using System.Web;
using System.Web.Helpers;
using System.Web.Http.Controllers;
using System.Web.Mvc;

namespace Angular4DotNetMVC.Models
{
    public WoUser[] GetUsers()
    {
        MyScreensEntities xEntity = new MyScreensEntities();
        List<User> xList = new List<User>();
        List<WoUser> userList = new List<WoUser>();

        xList = (from x in xEntity.Users select x).Take(20).ToList();
        if (xList != null)
        {
            foreach (User obj in xList)
            {
                WoUser yUser = new WoUser();
                yUser.Userid = obj.UserID;
                yUser.Userfirstname = obj.UserFirstname;
                yUser.Userlastname = obj.UserLastname;
                userList.Add(yUser);

            }
        }            
        WoUser[] myArray = userList.ToArray();
        return myArray;
    }
}
}

this is my controller

namespace Angular4DotNetMVC.Controllers
{
public class UserController : ApiController
{
    private RegistrationVmBuilder obj = new RegistrationVmBuilder();

    public WoUser[] Get()
    {
        return obj.GetUsers();
    }
}
}