curl --request GET \
  --url https://api.voucherify.io/v2/loyalties/tier-structures/{id}/activities \
  --header 'Authorization: Bearer <token>' \
  --header 'X-App-Id: <api-key>' \
  --header 'X-App-Token: <api-key>'

{
  "data": [
    {
      "id": "<string>",
      "tier_structure_id": "<string>",
      "type": "vl.tier_structure.created",
      "data": {},
      "created_at": "2023-11-07T05:31:56Z",
      "group_id": "<string>",
      "source": {
        "channel": "USER_PORTAL",
        "user": {
          "id": "<string>"
        },
        "api_key": {
          "name": "<string>",
          "app_id": "<string>",
          "client_app_id": "<string>"
        }
      }
    }
  ],
  "object": "list",
  "cursor": {
    "next": "<string>",
    "expires_at": "2023-11-07T05:31:56Z"
  }
}