curl --request POST \
  --url https://{host}/Agent/Xmpp/SendPresenceUnsubscription \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "to": "<string>",
  "id": "<string>"
}
'

{
  "sent": true,
  "id": "<string>"
}