const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};

fetch('https://api.keystoneos.xyz/v1/admin/settlements/transitions', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

{
  "period": "<string>",
  "transitions": [
    {
      "from_state": "<string>",
      "to_state": "<string>",
      "count": 123
    }
  ]
}