curl --request GET \
  --url https://api.example.com/distribution/delegators/{delegator_address}/rewards

{
  "code": 123,
  "msg": {
    "rewards": [
      {
        "validator_address": "<string>",
        "reward": "<unknown>"
      }
    ],
    "total": "<unknown>"
  },
  "error": "<string>"
}