Undefined variable $cartProductsKhipu

Hello,

I can notice a Warning in logs:

Undefined variable $cartProductsKhipu

in WC_Gateway_khipu_abstract::create_payment called at /public_html/wp-content/plugins/woocommerce-khipu/includes/class-wc-gateway-khipu-regular-transfer.php (153)
in WC_Gateway_khipu_regular_transfer::receipt_page called at /public_html/wp-includes/class-wp-hook.php (324)
in WP_Hook::apply_filters called at /public_html/wp-includes/class-wp-hook.php (348)
in WP_Hook::do_action called at /public_html/wp-includes/plugin.php (517)
in do_action called at /public_html/wp-content/plugins/woocommerce/templates/checkout/order-receipt.php (44)
in include called at /public_html/wp-content/plugins/woocommerce/includes/wc-core-functions.php (345)
in wc_get_template called at /public_html/wp-content/plugins/woocommerce/includes/shortcodes/class-wc-shortcode-checkout.php (245)
in WC_Shortcode_Checkout::order_pay called at /public_html/wp-content/plugins/woocommerce/includes/shortcodes/class-wc-shortcode-checkout.php (61)
in WC_Shortcode_Checkout::output called at /public_html/wp-content/plugins/woocommerce/includes/class-wc-shortcodes.php (72)
in WC_Shortcodes::shortcode_wrapper called at /public_html/wp-content/plugins/woocommerce/includes/class-wc-shortcodes.php (95)
in WC_Shortcodes::checkout called at /public_html/wp-includes/shortcodes.php (433)
in do_shortcode_tag called at ? (?)
in preg_replace_callback called at /public_html/wp-includes/shortcodes.php (273)
in do_shortcode called at /public_html/wp-includes/class-wp-hook.php (324)
in WP_Hook::apply_filters called at /public_html/wp-includes/plugin.php (205)
in apply_filters called at /public_html/wp-includes/post-template.php (256)
in the_content called at /public_html/wp-content/themes/flatsome/woocommerce/checkout/layouts/checkout.php (18)
in require called at /public_html/wp-includes/template.php (812)
in load_template called at /public_html/wp-content/plugins/woocommerce/includes/wc-core-functions.php (284)
in wc_get_template_part called at /public_html/wp-content/themes/flatsome/page-checkout.php (9)

Khipu 3.5

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