Produce error logs

Hello,

I am surprising the plugin is one of woocommerce product that does not update for 2 years. I have woocommerce v3.2.1.

The plugin Version 1.2 I have now produce php error logs when activate it. Error logs read:
[Oct 25, 00:54:58] price was called incorrectly. Product properties should not be accessed directly. Backtrace: require(‘wp-blog-header.php’), require_once(‘wp-includes/template-loader.php’), do_action(‘template_redirect’), WP_Hook->do_action, WP_Hook->apply_filters, WC_AJAX::do_wc_ajax, do_action(‘wc_ajax_update_order_review’), WP_Hook->do_action, WP_Hook->apply_filters, WC_AJAX::update_order_review, WC_Cart->calculate_totals, WC_Cart_Totals->__construct, WC_Cart_Totals->calculate, WC_Cart_Totals->calculate_fee_totals, WC_Cart_Totals->get_fees_from_cart, WC_Cart->calculate_fees, do_action(‘woocommerce_cart_calculate_fees’), WP_Hook->do_action, WP_Hook->apply_filters, WooCommerce_Product_Fees->add_fees, WC_Abstract_Legacy_Product->__get, wc_doing_it_wrong. This message was added in version 3.0.
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No error logs after deactivate it.

Please advise. Thanks in advance!