curl --request GET \
  --url https://app.flowglad.com/api/v1/purchases/{id} \
  --header 'Authorization: <api-key>'

{
  "purchase": {
    "id": "<string>",
    "createdAt": 0,
    "updatedAt": 0,
    "livemode": true,
    "name": "<string>",
    "status": "open",
    "customerId": "<string>",
    "organizationId": "<string>",
    "billingCycleAnchor": 0,
    "priceId": "<string>",
    "quantity": 123,
    "priceType": "<string>",
    "trialPeriodDays": 4503599627370495,
    "pricePerBillingCycle": 123,
    "intervalUnit": "day",
    "intervalCount": 123,
    "firstInvoiceValue": 4503599627370495,
    "totalPurchaseValue": null,
    "bankPaymentOnly": true,
    "purchaseDate": 0,
    "endDate": 0,
    "proposal": "<string>",
    "archived": true,
    "billingAddress": {
      "name": "<string>",
      "firstName": "<string>",
      "lastName": "<string>",
      "email": "jsmith@example.com",
      "address": {
        "name": "<string>",
        "line1": "<string>",
        "line2": "<string>",
        "city": "<string>",
        "state": "<string>",
        "postal_code": "<string>",
        "country": "<string>"
      },
      "phone": "<string>"
    },
    "metadata": {},
    "position": 123
  }
}