Permanently deletes a ticket; this cannot be undone. Also deletes every ticket marked as its duplicate, along with all messages, scheduled replies, console/network logs and replay data, and removes the ticket from other tickets' linked lists. Tickets combined with PUT /tickets/merge are archived and linked, not deleted.

Fires the TICKET_DELETED webhook and the S2S conversation.deleted event for this ticket only, not for the duplicates deleted with it. The same events fire when archive retention deletes a ticket. Tickets deleted together with their contact send no event; to catch every deletion, periodically compare the IDs from GET /tickets/csv-export (projection[]=_id, no type). Returns an empty body.