Fatal error: Uncaught Error: Call to a member function exists() on boolean in /usr/home/roc35.com/web/wp-content/plugins/woocommerce-pdf-product-vouchers/includes/class-wc-pdf-product-vouchers-product.php:176 Stack trace: #0 /usr/home/roc35.com/web/wp-content/plugins/woocommerce-pdf-product-vouchers/includes/class-wc-pdf-product-vouchers-cart.php(71): WC_PDF_Product_Vouchers_Product::has_voucher(false) #1 /usr/home/roc35.com/web/wp-includes/class-wp-hook.php(298): WC_PDF_Product_Vouchers_Cart->add_to_cart_validation(true, 5084, 1, 8643, Array) #2 /usr/home/roc35.com/web/wp-includes/plugin.php(203): WP_Hook->apply_filters(true, Array) #3 /usr/home/roc35.com/web/wp-content/plugins/woocommerce/includes/class-wc-form-handler.php(854): apply_filters('woocommerce_add...', true, 5084, 1, 8643, Array) #4 /usr/home/roc35.com/web/wp-content/plugins/woocommerce/includes/class-wc-form-handler.php(708): WC_Form_Handler::add_to_cart_handler_variable(5084) #5 /usr/home/roc35.com/web/wp-includes/class-wp-hook.php(298): WC_Form_Handler::a in /usr/home/roc35.com/web/wp-content/plugins/woocommerce-pdf-product-vouchers/includes/class-wc-pdf-product-vouchers-product.php on line 176