Appointment cancelled subscribe example:

curl --location --request POST '/platform/v1/webhook/subscribe' \
--header 'Authorization: "Bearer API_TOKEN"'\
--header 'Content-Type: application/json' \
--data-raw '{
"event": "appointment/cancelled",
"target_url": "URL"
}'

Appointment cancelled payload example:

{
  "entity_name": "appointment",
  "event_type": "cancelled",
  "data": {
    "business_id": "j9q05nvfv12w79vl",
    "appointment_id": "3in0a3b32nut67l6",
    "conversation_id": "pto6yng4e908c8g0",
    "title": "Introductory Phone Call",
    "client_id": "54gjvtadfbxiom7y",
    "staff_id": "e6j4i1ofy2pf0dmg",
    "start_time": "2019-10-29T10:00:00.000+02:00",
    "end_time": "2019-10-29T10:30:00.000+02:00",
    "duration": 30,
    "service_uid": "02nbrfqxys1gmoj2",
    "notes": "",
    "interaction_details": "123456",
    "currency": "ILS",
    "payment_id": null,
    "where": "phone",
    "source_data": {
      "id": 215954943,
      "name": "initiated_by_staff",
      "channel": null,
      "campaign": null,
      "website_url": null
      }
    },
    "phone_for_meeting": "123456"
  }