Rails - Unknown attribute password

I am following the Michael Michael Hartl Ruby on Rails tutorial to try and add users to my application. Reading chapter 6, I added that, in my opinion, the necessary fields for my user, in particular, password confirmation and password using "has_secure_password".

I thought that adding "has_secure_password" to my user model would include the attributes "password" and "password_confirmation" if I added "password_digest" to the model. I did it as the book taught. However, when I run the test, Rails gives me the following error:

Error:
UserTest#test_should_be_valid:
ActiveModel::UnknownAttributeError: unknown attribute 'password' for User.
    test/models/user_test.rb:8:in `setup'

I tried this solution and still gave me the same error without recognizing the attributes "password" or "password_confirmation". I installed bcrypt using "gem install bcrypt" and included the following in my gem file:

gem 'bcrypt-ruby' ,: require => 'bcrypt'

I am using Rails 5 and it seems that "has_secure_password" does not provide the password attributes I need. Can someone see what I missed or did not make "has_secure_password" not working properly? Thanks

User Model:

class User < ApplicationRecord

  has_many :activities

  class User < ActiveRecord::Base

    attr_accessor :name, :email, :password, :password_confirmation
    has_secure_password

    validates :first_name, presence: true, length: {minimum: 1}
    validates :last_name, presence: true, length: {minimum: 1}
    validates :email, presence: true, uniqueness: true, length: {minimum: 5}
    validates :username, presence: true, uniqueness: true, length: {minimum: 1}
    validates :password_digest, length: {minimum: 6}
    validates :password, :confirmation => true, length: {minimum: 4}
    validates :password_confirmation, presence: true

    #-----------------------New Stuff ---------------------------------------
    acts_as_authentic do |c|
      c.crypto_provider = Authlogic::CryptoProviders::Sha512
    end
    #------------------------------------------------------------------------

    #---------------Unsure if working--------------
    #validates_presence_of :password, :on => :create
    #validates_presence_of :email
    #validates_uniqueness_of :email
    #----------------------------------------------

    def self.authenticate(email, password)
      user = find_by_email(email)
      if user && user.password_hash == BCrypt::Engine.hash_secret(password, user.password_salt)
        user
      else
        nil
      end
    end

    def encrypt_password
      if password.present?
        self.password_salt = BCrypt::Engine.generate_salt
        self.password_hash = BCrypt::Engine.hash_secret(password, password_salt)
      end
    end
  end
end

Apologies for the messy code of the model as I am still learning Rails.

User controller:

class UsersController < ApplicationController
  def new
    @user = User.new
  end

  def create
    @user = User.new(user_params)
    if @user.save
      flash[:success] = 'Account created'
    else
      flash[:notice] ='ERROR: Account was not created'
      redirect_to 'users/new'
    end
  end

  def show
    @user = User.find(params[:id])
  end


  private
  def user_params
    params.require(:user).permit(:first_name, :last_name, :email, :password, :password_confirmation)
  end
end

User table:

 create_table "users", force: :cascade do |t|
    t.string   "first_name"
    t.string   "last_name"
    t.string   "username"
    t.string   "email"
    t.datetime "created_at",        null: false
    t.datetime "updated_at",        null: false
    t.string   "persistence_token"
    t.string   "password_digest"
    t.index ["email"], name: "index_users_on_email", unique: true, using: :btree
  end

User test:

require 'test_helper'

class UserTest < ActiveSupport::TestCase
  # test "the truth" do
  #   assert true
  # end
  def setup
    @user = User.new(first_name: 'test', last_name: 'tester', password: '1234',email: 'test1@mail.com',
                     password: 'foobar', password_confirmation: 'foobar')
  end
  test 'should be valid' do
    assert @user.valid?
  end
end