Error entre woocommerce checkout field editor y Mipaquete

Hola, estoy recibiendo este error al usar el plugin woocommerce checkout field editor y el plugin de mi paquete. (tambien intenté con otro plugin similar y da un error parecido)

PHP Fatal error: Uncaught Error: Call to a member function get_cart() on null in /wp-content/plugins/shipping-mipaquete-woocommerce/includes/class-shipping-mipaquete-smw-plugin.php:142
Stack trace:
#0 /wp-includes/class-wp-hook.php(289): Shipping_Mipaquete_SMW_Plugin->custom_woocommerce_billing_fields(Array)
#1 /wp-includes/plugin.php(206): WP_Hook->apply_filters(Array, Array)
#2 /wp-content/plugins/woocommerce/includes/class-wc-countries.php(1451): apply_filters(‘woocommerce_bil…’, Array, ‘CO’)
#3 /wp-content/plugins/woocommerce-checkout-field-editor/includes/class-wc-checkout-field-editor.php(161): WC_Countries->get_address_fields(‘CO’, ‘billing_’)
#4 /wp-includes/class-wp-hook.php(287): WC_Checkout_Field_Editor->the_editor(”)
#5 /wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(”, Array)
#6 /wp-includes/p in /home/mkweejif/public_html/wp-content/plugins/shipping-mipaquete-woocommerce/includes/class-shipping-mipaquete-smw-plugin.php on line 142