curl --request GET \
  --url https://{cluster}.voucherify.io/v1/rewards/{rewardId}/assignments \
  --header 'X-App-Id: <api-key>' \
  --header 'X-App-Token: <api-key>'

{
  "object": "list",
  "data_ref": "data",
  "data": [
    {
      "id": "rewa_PbIRoMXpwe5QhobW4JKu0VjH",
      "reward_id": "rew_C7wS9eHFDN4CIbXI5PpLSkGY",
      "related_object_id": "camp_wciTvaOfYmAa3EmIIW3QpXXZ",
      "related_object_type": "campaign",
      "parameters": {
        "loyalty": {
          "points": 15
        }
      },
      "created_at": "2022-08-17T08:13:02.507Z",
      "updated_at": null,
      "object": "reward_assignment"
    },
    {
      "id": "rewa_pJYQBXSitK2OVPK3XMXZK76X",
      "reward_id": "rew_C7wS9eHFDN4CIbXI5PpLSkGY",
      "related_object_id": "camp_jcErmtGAOmHUAy0oUgkwKnPZ",
      "related_object_type": "campaign",
      "parameters": {
        "loyalty": {
          "points": 20
        }
      },
      "created_at": "2022-08-24T11:40:22.418Z",
      "updated_at": null,
      "object": "reward_assignment"
    }
  ],
  "total": 2
}

{
  "code": 404,
  "key": "not_found",
  "message": "Resource not found",
  "details": "Cannot find reward with id rew_C7wS9eHFDN4CIbXI5PpLSkGYi",
  "request_id": "v-0b95a68c678ad5c765",
  "resource_id": "rew_C7wS9eHFDN4CIbXI5PpLSkGYi",
  "resource_type": "reward"
}