curl --request GET \
  --url https://api.test.doola.com/v1/partner/customers/{customerId} \
  --header 'Authorization: <api-key>'

{
  "payload": {
    "doolaCustomerId": "<string>",
    "email": "founder@example.com",
    "firstName": "Ada",
    "lastName": "Lovelace",
    "countryOfResidence": "USA",
    "phoneNumber": "+12125550100",
    "created": true,
    "companies": [
      {
        "doolaCompanyId": "<string>",
        "name": "Acme Labs LLC",
        "entityType": "LLC",
        "state": "DE"
      }
    ]
  },
  "error": {}
}