Updates a template's title and default language, and at the same time either edits one of its language entries or adds a new one. Send is_new: true to add an entry; otherwise canned_response_text_uuid selects the entry to edit, and an id you leave out simply matches nothing while the call still succeeds. The text and the template are written in separate steps and no check is made that a row actually changed, so a 200 does not prove an entry was found. An id that does not match a canned response on your account changes nothing, but the response is still 200 with an empty object.