[EC-CUBE] 3.0.12-p1から3.0.16へアップデート
[レンタルサーバ] ロリポップ
[OS] Windows10
[PHP] 7.1 CGI
[データベース] ５.６
[ブラウザ] Chrome
[エラー内容] 商品をカートに入れてレジに進もうとするとエラーになります。デバッグモードでは下記のエラー内容が表示されます。恐れ入りますがご教示いただけますと幸いです。よろしくお願いいたします。

1/1
InvalidArgumentException in Pimple.php line 78:
Identifier "mobile_detect" is not defined.
in Pimple.php line 78
at Pimple->offsetGet('mobile_detect') in ShoppingService.php line 174
at ShoppingService->registerPreOrder(object(Customer), 'e37f3ded7e627c07d762a174027719a6682a157c') in ShoppingService.php line 147
at ShoppingService->createOrder(object(Customer)) in ShoppingController.php line 111
at ShoppingController->index(object(Application), object(Request))
at call_user_func_array(array(object(ShoppingController), 'index'), array(object(Application), object(Request))) in HttpKernel.php line 144
at HttpKernel->handleRaw(object(Request), '1') in HttpKernel.php line 64
at HttpKernel->handle(object(Request), '1', true) in Application.php line 586
at Application->handle(object(Request)) in Application.php line 563
at Application->run() in index_dev.php line 104