curl --request GET \
  --url https://gateway.polymarket.us/v1/series/id/{id}

{
  "series": {
    "id": "<string>",
    "slug": "<string>",
    "title": "<string>",
    "subtitle": "<string>",
    "recurrence": "<string>",
    "image": "<string>",
    "active": true,
    "createdAt": "<string>",
    "updatedAt": "<string>"
  }
}