plugin generate php warnings

When plugin is activated and visiting a product page i get the next error, when i deactivate the plugin errors stops:
Notice: product_type was called incorrectly. Product properties should not be accessed directly. Backtrace: require(‘wp-blog-header.php’), require_once(‘wp-includes/template-loader.php’), include(‘/plugins/woocommerce/templates/single-product.php’), wc_get_template_part, load_template, require(‘/plugins/woocommerce/templates/content-single-product.php’), do_action(‘woocommerce_single_product_summary’), WP_Hook->do_action, WP_Hook->apply_filters, woocommerce_template_single_add_to_cart, do_action(‘woocommerce_variable_add_to_cart’), WP_Hook->do_action, WP_Hook->apply_filters, woocommerce_variable_add_to_cart, wc_get_template, include(‘/plugins/woocommerce/templates/single-product/add-to-cart/variable.php’), do_action(‘woocommerce_before_add_to_cart_button’), WP_Hook->do_action, WP_Hook->apply_filters, product_page_options_class->display_product_options, WC_Abstract_Legacy_Product->__get, wc_doing_it_wrong Please see Debugging in WordPress/var/www/wp-includes/functions.php on line 4147

Notice: id was called incorrectly. Product properties should not be accessed directly. Backtrace: require(‘wp-blog-header.php’), require_once(‘wp-includes/template-loader.php’), include(‘/plugins/woocommerce/templates/single-product.php’), wc_get_template_part, load_template, require(‘/plugins/woocommerce/templates/content-single-product.php’), do_action(‘woocommerce_single_product_summary’), WP_Hook->do_action, WP_Hook->apply_filters, woocommerce_template_single_add_to_cart, do_action(‘woocommerce_variable_add_to_cart’), WP_Hook->do_action, WP_Hook->apply_filters, woocommerce_variable_add_to_cart, wc_get_template, include(‘/plugins/woocommerce/templates/single-product/add-to-cart/variable.php’), do_action(‘woocommerce_before_add_to_cart_button’), WP_Hook->do_action, WP_Hook->apply_filters, product_page_options_class->display_product_options, WC_Abstract_Legacy_Product->__get, wc_doing_it_wrong Please see Debugging in WordPress for more in /var/www/wp-includes/functions.php on line 4147

Notice: product_type was called incorrectly. Product properties should not be accessed directly. Backtrace: require(‘wp-blog-header.php’), require_once(‘wp-includes/template-loader.php’), include(‘/plugins/woocommerce/templates/single-product.php’), wc_get_template_part, load_template, require(‘/plugins/woocommerce/templates/content-single-product.php’), do_action(‘woocommerce_single_product_summary’), WP_Hook->do_action, WP_Hook->apply_filters, woocommerce_template_single_add_to_cart, do_action(‘woocommerce_variable_add_to_cart’), WP_Hook->do_action, WP_Hook->apply_filters, woocommerce_variable_add_to_cart, wc_get_template, include(‘/plugins/woocommerce/templates/single-product/add-to-cart/variable.php’), do_action(‘woocommerce_before_add_to_cart_button’), WP_Hook->do_action, WP_Hook->apply_filters, product_page_options_class->display_product_options, WC_Abstract_Legacy_Product->__get, wc_doing_it_wrong Please see Debugging in WordPress/var/www/wp-includes/functions.php on line 4147

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