Sorry if I made myself unclear. So as a whole. I want that when a ticket is closed in Youtrack, the person in Zammad gets an automatic message that we are finished and their error will be fixed. However, in Youtrack there is only a link to the ticket. Therefore, an API request would either have to obtain the email address automatically or be able to respond to the customer’s message. I manage to get a message written, but then no email is sent to the customer. Therefore, it seems to me that there is still a step missing with the mailing
Setting the to attribute is mandatory and does not happen automatically.
That’s because a ticket is not limitted to one conversation partner and that partner could change due to internal questions to others by e.g. your customer.
So you may have to shoot a second request to find out who you’re talking to actually.