Shipping confirmation email sent to customers

Hi ,

I would like to set shipping confirmation email option when an order is shipped out.
Preconditions and the options I tried:

  • custom integration and no manual setting present in the admin (confirmed with veeqo via chat and it seems that custom integrations have limited options).
  • we sent an api call with the below field set to true:
    send_notification_emails_to_customers
    The response included in this field was set to true, so we assumed this should work now, but it is not - which means it did not trigger the automatic notification emails.
    Have missed any other settings/attributes perhaps?