curl --request GET \
  --url https://api.heyy.io/api/v2.0/contacts \
  --header 'Authorization: Bearer <token>'

{
  "data": {
    "contacts": [
      {
        "id": "<string>",
        "createdAt": "<string>",
        "updatedAt": "<string>",
        "firstName": "<string>",
        "lastName": "<string>",
        "phoneNumber": "<string>",
        "email": "<string>",
        "labels": [
          "<string>"
        ],
        "attributes": [
          {
            "name": "<string>",
            "value": "<string>"
          }
        ]
      }
    ]
  }
}