curl --request GET \
  --url https://api.upwell.com/api/rest/customers/{id}

{
  "customer": {
    "addresses": [
      {
        "city": "<string>",
        "country": "AD",
        "id": "<string>",
        "stateOrProvince": "<string>",
        "streetLine1": "<string>",
        "streetLine2": "<string>",
        "type": "ADDRESS_BOOK",
        "zipOrPostalCode": "<string>"
      }
    ],
    "balance": 123,
    "billToCustomerId": "<string>",
    "ccEmailAddresses": [
      "<string>"
    ],
    "createdAt": "2023-11-07T05:31:56Z",
    "customerRule": {
      "dueOption": 123,
      "id": "<string>"
    },
    "emailAddress": "<string>",
    "id": "<string>",
    "metadata": "<unknown>",
    "name": "<string>",
    "overdueBalance": 123,
    "overdueInvoiceCount": 123,
    "sourceSystem": "<string>",
    "sourceSystemId": "<string>",
    "updatedAt": "2023-11-07T05:31:56Z"
  }
}