[Refer A Friend] Make referral coupons into free-gift coupons

functions.php

<?php

add_filter( 'automatewoo/referrals/coupon_data', 'my_automatewoo_referrals_free_gift_coupon_data', 10, 4 );

/**
 * Make AutomateWoo Refer A Friend coupons free gift coupons.
 *
 * REQUIRES: WooCommerce v3.6 and Refer A Friend v2.3.1
 * REQUIRES: https://woocommerce.com/products/free-gift-coupons/
 *
 * @param array     $coupon_data
 * @param string    $coupon_code
 * @param int       $advocate_id
 * @param WC_Coupon $coupon
 *
 * @return array
 */
function my_automatewoo_referrals_free_gift_coupon_data( $coupon_data, $coupon_code, $advocate_id, $coupon ) {
	$coupon_data['discount_type'] = 'free_gift';

	// defines the product ID/s that will be free
	$coupon->update_meta_data( 'gift_ids', [27,26] );

	// defines whether shipping should be free
	$coupon->update_meta_data( 'free_gift_shipping', false );

	return $coupon_data;
}

Hello mr. Daniel,

I was looking for a fix to achieve just this and was happy to find your code. But when I implement it, it does not work.
How can I achieve this fix?

Thank you in advance