Delivery Date is a required field

Hi,
I’m using your plugin which is very good. Recently I started to use WC Autoship and the scheduled payment always failed. I find out that this is because this error
The error returned is
“Delivery Date is a required field”
This is a custom field that is not part of WC Autoship. This field must be added to WC Autoship with custom scripting

<?php
/**
* @param array $order_data
* @param int $customer_id
* @param string $shipping_method
* @param string $payment_gateway_id
* @param string $payment_token_id
* @return array 
*/
function wc_autoship_checkout_order_data_example( $order_data, $customer_id, $shipping_method, $payment_gateway_id, $payment_token_id ) {
  // Add a custom field to order_data
  $order_data['my_custom_field'] = 'my_custom_value';
  return $order_data;
}
add_filter( 'wc_autoship_checkout_order_data', 'wc_autoship_checkout_order_data_example', 10, 5 );

Can you please help what I should put in my_custom_field and my_custom_value

Regards,
Michal

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