[EC-CUBE] EC-CUBE4系
[レンタルサーバ] さくらインターネット
[PHP] PHP7.3
[ブラウザ] Chrome、Safari

[現象]
管理画面のブロック管理や商品管理の画面から変更→登録ボタンを押すと自動的にシステムエラーが発生しました。の画面になります。
そこで再度、ログインすると変更が反映されています。

[やったこと]
キャッシュの問題かと思い一度、FTPと管理画面からキャッシュの削除を行いましたが変わらずでした...
プラグインも一度停止しましたが治らずです。

[最近のエラーログ]
[2020-10-21 14:22:31] app.INFO [N/A] [326a038] [1] [Eccube\Log\Logger:log:68] - PROCESS END ["admin_setting_system_log"] [GET, /uhouho/setting/system/log, ドメイン名/uhouho/store/plugin, Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_5) AppleWebKit (KHTML, like Gecko) Chrome Safari]
[2020-10-21 14:00:02] app.INFO [N/A] [dab6ab4] [1] [Eccube\Log\Logger:log:68] - PROCESS END ["admin_store_plugin"] [GET, /uhouho/store/plugin, ドメイン名/uhouho/setting/shop/delivery/2/edit, Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_5) AppleWebKit/(KHTML, like Gecko) Chrome/Safari/]

どなたかお助けください

ログファイルにはエラー以外のログも多く記載されており、
それら app.INFOとなっているのは大抵エラーとは関係ないと思います。
システムエラーとなっている行はないでしょうか？

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EC-CUBEカスタマイズ・高速化・脆弱性対策・SEO ご相談ください。

2系・3系から4系へのバージョンアップ実績豊富

ご返信ありがとうございます。こちらがエラーログです。

[2020-10-22 14:09:20] php.INFO [b5b2cd3c] [f218464] [1] [Symfony\Component\Debug\ErrorHandler:handleError:532] - User Deprecated: The "Eccube\Service\Composer\ComposerApiService" service is private, getting it from the container is deprecated since Symfony 3.2 and will fail in 4.0. You should either make the service public, or stop using the container directly and use dependency injection instead. {"exception":"[object] (ErrorException(code: 0): User Deprecated: The \"Eccube\\Service\\Composer\\ComposerApiService\" service is private, getting it from the container is deprecated since Symfony 3.2 and will fail in 4.0. You should either make the service public, or stop using the container directly and use dependency injection instead. at /ドメイン名/vendor/symfony/dependency-injection/Container.php:282)"} [POST, /uhouho/product/product/29/edit, ドメイン名/uhouho/product/product/29/edit, Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_5) AppleWebKit/ (KHTML, like Gecko) Chrome/ Safari]
[2020-10-22 14:09:20] php.INFO [b5b2cd3c] [f218464] [1] [Symfony\Component\Debug\ErrorHandler:handleError:532] - User Deprecated: The "doctrine.app_cache_pool" service is private, checking for its existence is deprecated since Symfony 3.2 and will fail in 4.0. {"exception":"[object] (ErrorException(code: 0): User Deprecated: The \"doctrine.app_cache_pool\" service is private, checking for its existence is deprecated since Symfony 3.2 and will fail in 4.0. at /ドメイン名/vendor/symfony/dependency-injection/Container.php:224)"} [POST, /uhouho/product/product/29/edit, ドメイン名/uhouho/product/product/29/edit, Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_5) AppleWebKit/ (KHTML, like Gecko) Chrome/ Safari/]
[2020-10-22 14:09:20] php.INFO [b5b2cd3c] [f218464] [1] [Symfony\Component\Debug\ErrorHandler:handleError:532] - User Deprecated: Calling Doctrine\ORM\EntityManager::flush() with any arguments to flush specific entities is deprecated and will not be supported in Doctrine ORM 3.0. {"exception":"[object] (ErrorException(code: 0): User Deprecated: Calling Doctrine\\ORM\\EntityManager::flush() with any arguments to flush specific entities is deprecated and will not be supported in Doctrine ORM 3.0. at /ドメイン名/vendor/doctrine/orm/lib/Doctrine/ORM/EntityManager.php:362)"} [POST, /uhouho/product/product/29/edit, ドメイン名/uhouho/product/product/29/edit, Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_5) AppleWebKit/ (KHTML, like Gecko) Chrome/Safari/]
[2020-10-22 14:09:15] app.INFO [N/A] [e594d01] [1] [Eccube\Log\Logger:log:68] - PROCESS END ["admin_product_product_edit"] [GET, /uhouho/product/product/29/edit, ドメイン名/uhouho/product, Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_5) AppleWebKit/ (KHTML, like Gecko) Chrome/ Safari/]
[2020-10-22 14:09:13] app.INFO [N/A] [c9cd88e] [1] [Eccube\Log\Logger:log:68] - PROCESS END ["admin_product"] [GET, /uhouho/product, ドメイン名/uhouho/setting/system/log, Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_5) AppleWebKit/ (KHTML, like Gecko) Chrome/ Safari]