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

fetch('http://localhost:4000/v1/customers/{id}', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

curl --request GET \
  --url http://localhost:4000/v1/customers/{id} \
  --header 'Authorization: Bearer <token>'

{
  "id": "cus_4Kq9Lm2Np7RsTv",
  "object": "customer",
  "email": "<string>",
  "wallet_address": "<string>",
  "default_payment": "ausd",
  "livemode": true,
  "created": 123,
  "subscription_count": 123,
  "total_settled_usd": "<string>"
}

{
  "error": {
    "type": "api_error",
    "message": "<string>",
    "code": "<string>",
    "param": "<string>"
  }
}

{
  "error": {
    "type": "api_error",
    "message": "<string>",
    "code": "<string>",
    "param": "<string>"
  }
}

{
  "error": {
    "type": "api_error",
    "message": "<string>",
    "code": "<string>",
    "param": "<string>"
  }
}