开拓者装载合同问题

我正在学习本教程https://medium.com/@acesubido/adding-by-factor-authentication-in-activeadmin-2ed134b60042

为了设置2FA，在这种情况下，我需要为用户设置Trailblazer。在本教程中，它解释了如何为ActiveAdmin添加2FA。

我有以下宝石：

gem 'devise-two-factor' # 2FA auth
gem 'rqrcode'           # Generates a QR code
gem 'trailblazer', '~> 2.1', '>= 2.1.2'
gem "trailblazer-rails"

我已经有了操作和合同文件夹。它们看起来像这样：

app/concepts/user/contracts/setup_two_factor.rb

app/concepts/user/operation/setup_two_factor.rb

这是我的operation的样子：

module User::Operation
  class SetupTwoFactor < Trailblazer::Operation

      step Model(User, :find)
      step Contract::build(constant: User::Contracts::SetupTwoFactor)
      step Contract::Validate(key: :user)
      step Contract::Persist(method: :sync)
      success :set_otp_secret!
      step Contract::Persist(method: :save)

    def set_otp_secret!(options, params:, **)
      if options['model'].otp_required_for_login
        unless options['model'].otp_secret.present?
          options['model'].otp_secret = User.generate_otp_secret
        end
      end
    end
  end
end

这就是我的contracts的样子：

module User::Contract
  class SetupTwoFactor < Reform::Form

    property :otp_required_for_login

  end
end

问题

My 问题 comes that, whenever I want to click on the save button. (Image Below)

I get this 问题:

I've check the documentation and everything but can't seem to find the 问题.