Fatal error: Uncaught Error: Call to undefined function is_checkout() in /www_root/wp-content/plugins/cosmosfarm-quick-buy-woocomerce/class/Cosmosfarm_Quick_Buy_Woocommerce_Controller.class.php:82 Stack trace: #0 /www_root/wp-includes/class-wp-hook.php(308): Cosmosfarm_Quick_Buy_Woocommerce_Controller->cosmosfarm_quick_buy_add_product_to_checkout('') #1 /www_root/wp-includes/class-wp-hook.php(332): WP_Hook->apply_filters(NULL, Array) #2 /www_root/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #3 /www_root/wp-includes/template-loader.php(13): do_action('template_redire...') #4 /www_root/wp-blog-header.php(19): require_once('/www_root/wp-in...') #5 /www_root/index.php(17): require('/www_root/wp-bl...') #6 {main} thrown in /www_root/wp-content/plugins/cosmosfarm-quick-buy-woocomerce/class/Cosmosfarm_Quick_Buy_Woocommerce_Controller.class.php on line 82

이런 오류 메세지가 나왔습니다.

그리고 비활성화했더니 레이아웃이 깨지는 문제가 발생합니다

오류 해결방법 및 레이아웃 복원할 수 있는 방법이 있나요?

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