Rails,AWS(IAM:ユーザ, S3:バケット),herokuでの画像アップロードエラー(AccessDenied)解消

Question

前提

Rails,AWS(IAM:ユーザ, S3:バケット),herokuでCRUDなシステムを作っています。
画像アップロード機能を実装後の動作確認中に以下のエラーメッセージが発生しました。
申し訳ございませんが、ご確認よろしくお願いします。

実現したいこと

Rails,AWS(IAM:ユーザ, S3:バケット),herokuで新規登録時の
画像アップロードエラー(AccessDenied)解消

発生している問題・エラーメッセージ

(Expected(204) <=> Actual(403 Forbidden)

<Code>AccessDenied</Code><Message>Access Denied</Message>

該当のソースコード

source 'https://rubygems.org'
git_source(:github) { |repo| "https://github.com/#{repo}.git" }

ruby '2.6.9'

# Bundle edge Rails instead: gem 'rails', github: 'rails/rails', branch: 'main'
gem 'rails', '~> 6.1.6'
# Use sqlite3 as the database for Active Record
#gem 'sqlite3', '~> 1.4'
# Use Puma as the app server
gem 'puma', '~> 5.0'
# Use SCSS for stylesheets
gem 'sass-rails', '>= 6'
# Transpile app-like JavaScript. Read more: https://github.com/rails/webpacker
gem 'webpacker', '~> 5.0'
# Turbolinks makes navigating your web application faster. Read more: https://github.com/turbolinks/turbolinks
gem 'turbolinks', '~> 5'
# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
gem 'jbuilder', '~> 2.7'
# Use Redis adapter to run Action Cable in production
# gem 'redis', '~> 4.0'
# Use Active Model has_secure_password
# gem 'bcrypt', '~> 3.1.7'

# Use Active Storage variant
# gem 'image_processing', '~> 1.2'

# Reduces boot times through caching; required in config/boot.rb
gem 'bootsnap', '>= 1.4.4', require: false

group :development, :test do
  gem 'sqlite3', '~> 1.4'
  # Call 'byebug' anywhere in the code to stop execution and get a debugger console
  gem 'byebug', platforms: [:mri, :mingw, :x64_mingw]

  gem 'rspec-rails'

  gem 'factory_bot_rails'

end

group :development do
  # Access an interactive console on exception pages or by calling 'console' anywhere in the code.
  gem 'web-console', '>= 4.1.0'
  # Display performance information such as SQL time and flame graphs for each request in your browser.
  # Can be configured to work on production as well see: https://github.com/MiniProfiler/rack-mini-profiler/blob/master/README.md
  gem 'rack-mini-profiler', '~> 2.0'
  gem 'listen', '~> 3.3'
  # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
  gem 'spring'

  gem "rails-erd"

end

group :production do
  gem 'pg'
end

group :test do
  # Adds support for Capybara system testing and selenium driver
  gem 'capybara', '>= 3.26'
  gem 'selenium-webdriver', '>= 4.0.0.rc1'
  # Easy installation and use of web drivers to run system tests with browsers
  gem 'webdrivers'
end

# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]

gem 'devise'

gem 'ransack'

gem 'kaminari'

gem 'carrierwave', '~> 2.0'

gem 'mini_magick'

gem 'fog-aws'
gem "aws-sdk-s3", require: false

gem 'dotenv-rails'

require 'carrierwave/storage/abstract'
require 'carrierwave/storage/file'
require 'carrierwave/storage/fog'

CarrierWave.configure do |config|
  config.storage :fog
  config.fog_provider = 'fog/aws'
  config.fog_directory  = 'mportfolio-bucket'
  config.fog_credentials = {
    provider: 'AWS',
    aws_access_key_id: ENV['AWS_ACCESS_KEY_ID'],
    aws_secret_access_key: ENV['AWS_SECRET_ACCESS_KEY'],
    region: ENV['AWS_DEFAULT_REGION'],
    path_style: true
  }

end

test:
  service: Disk
  root: <%= Rails.root.join("tmp/storage") %>

local:
  service: Disk
  root: <%= Rails.root.join("storage") %>
# Use rails credentials:edit to set the AWS secrets (as aws:access_key_id|secret_access_key)
amazon:
  service: S3
  access_key_id: <%= Rails.application.credentials.dig(:aws, :access_key_id) %>
  secret_access_key: <%= Rails.application.credentials.dig(:aws, :secret_access_key) %>
  region: ap-northeast-1
  bucket: 自分のバケット名

config.active_storage.service = :amazon

class ImageUploader < CarrierWave::Uploader::Base
  # Include RMagick or MiniMagick support:
  # include CarrierWave::RMagick
  include CarrierWave::MiniMagick

  # Choose what kind of storage to use for this uploader:
  # storage :file
  # storage :fog
  if Rails.env.development?
    storage :file
  elsif Rails.env.test?
    storage :file
  else
    storage :fog
  end

  # Override the directory where uploaded files will be stored.
  # This is a sensible default for uploaders that are meant to be mounted:
  def store_dir
    "uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
  end

  # Provide a default URL as a default if there hasn't been a file uploaded:
  def default_url(*args)
  #   # For Rails 3.1+ asset pipeline compatibility:
  ActionController::Base.helpers.asset_path("fallback/" + [version_name, "default.png"].compact.join('_'))
  #
  #   "/images/fallback/" + [version_name, "default.png"].compact.join('_')
  end

  version :thumb do
    process resize_to_fit: [50, 50]
  end

end

試したこと

下記２リンク手順参考にAWS(IAM:ユーザ, S3:バケット)などの設定後、
heroku上にアプリデプロイを行い、画像アップロードの動作確認(新規登録)を実施。

・Rails, Laravel(画像アップロード)向けAWS(IAM:ユーザ, S3:バケット)の設定
https://qiita.com/nobu0717/items/4425c02157bc5e88d7b6

・【初学者必見】 HerokuとAWS S3を連携して投稿画像を保持する方法
https://qiita.com/jibiking/items/0e8c1d826271ac9e4a7d#%E9%96%8B%E7%99%BA%E7%92%B0%E5%A2%83--%E5%89%8D%E6%8F%90%E6%9D%A1%E4%BB%B6

補足情報（FW/ツールのバージョンなど）

上記２リンク手順でAWS(IAM:ユーザ, S3:バケット)などの設定後、
heroku上にアプリデプロイを行い、画像アップロードの動作確認(新規登録)を行ったところエラー画面が表示。
ただ、エラー後にもう一度herokuにログインすると新規追加は成功されており（画像も表示）、
s3にも画像は保存されてはいます。

Answer 1

解決いたしました、ありがとうございます。