rake s3_direct_upload:clean_remote_uploads not working

[zulhfreelancer]

After I install fog gem and run rake s3_direct_upload:clean_remote_uploads command, I get this:

And when I check my S3 bucket, they are not deleted:

Am I missing something?

This is my Gemfile:

source 'https://rubygems.org'

gem 'rails', '4.0.6'
gem 'pg'
gem 'sass-rails', '~> 4.0.2'
gem 'uglifier', '>= 1.3.0'
gem 'coffee-rails', '~> 4.0.0'
gem 'jquery-rails'
gem 'turbolinks'
gem 'jbuilder', '~> 1.2'
gem 'devise'
gem 'slim'
gem 'jumpup',        '0.0.3'
gem 'jumpup-heroku', '0.0.3'
gem 'paperclip', '~> 4.0'
gem 'bootstrap-sass', '~> 3.1.0'
gem 's3_direct_upload', '0.1.6'
gem 'aws-sdk', '~> 1.0'

# not for uploading file to s3, but for cleaning old uploads on s3
gem 'fog'

group :production do
  gem 'rails_12factor'
end

group :development, :test do
  gem 'rspec-rails', '~> 3.0.0.beta'
  gem 'factory_girl_rails'
  gem 'dotenv-rails'
  gem 'pry-rails'
end

group :test do
  gem 'simplecov'
  gem 'shoulda-matchers'
  gem 'vcr', '2.8.0'
  gem 'webmock', '< 1.16'
end