Depreciated WordPress code

root@web01 ~ # tail -f /home/myaccount/logs/mydomain_com.php.error.log
[20-Jun-2019 02:38:26 UTC] PHP Notice: Array to string conversion in /home/myaccount/public_html/wp-content/plugins/woofunnels-woocommerce-nmi-gateway/woofunnels/contact/class-woofunnels-db-operations.php on line 241
[20-Jun-2019 02:38:26 UTC] PHP Notice: Array to string conversion in /home/myaccount/public_html/wp-content/plugins/woofunnels-woocommerce-nmi-gateway/woofunnels/contact/class-woofunnels-db-operations.php on line 241
[20-Jun-2019 02:38:26 UTC] PHP Warning: preg_replace(): Compilation failed: invalid range in character class at offset 4 in /home/myaccount/public_html/wp-content/plugins/woofunnels-woocommerce-nmi-gateway/includes/api/requests/class-nmi-gateway-woocommerce-api-transaction-request.php on line 205
[20-Jun-2019 02:38:26 UTC] exp_year was called incorrectly. Order 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_checkout’), WP_Hook->do_action, WP_Hook->apply_filters, WC_AJAX::checkout, WC_Checkout->process_checkout, WC_Checkout->process_order_payment, SkyVerge\WooCommerce\PluginFramework\v5_2_1\SV_WC_Payment_Gateway_Direct->process_payment, SkyVerge\WooCommerce\PluginFramework\v5_2_1\SV_WC_Payment_Gateway_Direct->do_transaction, NMI_Gateway_Woocommerce_Credit_Card->do_credit_card_transaction, NMI_Gateway_Woocommerce_API->credit_card_charge, NMI_Gateway_Woocommerce_API_Transaction_Request->create_credit_card_charge, NMI_Gateway_Woocommerce_API_Transaction_Request->create_transaction, NMI_Gateway_Woocommerce_API_Transaction_Request->set_payment_method, WC_Abstract_Legacy_Order->__get, wc_doing_it_wrong. This message was added in version 3.0.
[20-Jun-2019 02:38:26 UTC] The WC_Order::get_order_currency function is deprecated since version 3.0. Replace with WC_Order::get_currency.
[20-Jun-2019 02:39:18 UTC] PHP Notice: Array to string conversion in /home/myaccount/public_html/wp-content/plugins/woofunnels-woocommerce-nmi-gateway/woofunnels/contact/class-woofunnels-db-operations.php on line 241
[20-Jun-2019 02:39:18 UTC] PHP Notice: Array to string conversion in /home/myaccount/public_html/wp-content/plugins/woofunnels-woocommerce-nmi-gateway/woofunnels/contact/class-woofunnels-db-operations.php on line 241
[20-Jun-2019 02:39:18 UTC] PHP Warning: preg_replace(): Compilation failed: invalid range in character class at offset 4 in /home/myaccount/public_html/wp-content/plugins/woofunnels-woocommerce-nmi-gateway/includes/api/requests/class-nmi-gateway-woocommerce-api-transaction-request.php on line 205
[20-Jun-2019 02:39:18 UTC] exp_year was called incorrectly. Order 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_checkout’), WP_Hook->do_action, WP_Hook->apply_filters, WC_AJAX::checkout, WC_Checkout->process_checkout, WC_Checkout->process_order_payment, SkyVerge\WooCommerce\PluginFramework\v5_2_1\SV_WC_Payment_Gateway_Direct->process_payment, SkyVerge\WooCommerce\PluginFramework\v5_2_1\SV_WC_Payment_Gateway_Direct->do_transaction, NMI_Gateway_Woocommerce_Credit_Card->do_credit_card_transaction, NMI_Gateway_Woocommerce_API->credit_card_charge, NMI_Gateway_Woocommerce_API_Transaction_Request->create_credit_card_charge, NMI_Gateway_Woocommerce_API_Transaction_Request->create_transaction, NMI_Gateway_Woocommerce_API_Transaction_Request->set_payment_method, WC_Abstract_Legacy_Order->__get, wc_doing_it_wrong. This message was added in version 3.0.
[20-Jun-2019 02:39:18 UTC] The WC_Order::get_order_currency function is deprecated since version 3.0. Replace with WC_Order::get_currency.

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