Event Calendar < 1.1.51 - Subscriber+ Event Creation

Adding calendar events:
fetch("https://example.com/wp-admin/admin-ajax.php", {
  "headers": {
    "content-type": "application/x-www-form-urlencoded",
  },
  "body": new URLSearchParams({"action": "add_calendar_event", "ecwd_calendar_id": 4, "ecwd_event_name": "An opening", "ecwd_date_from": "2021/11/01", "ecwd_date_to": "2022/11/01"}),
  "method": "POST",
  "credentials": "include"
})
  .then(response => response.text())
  .then(data => console.log(data));