{ "currency": "string", "gst": true, "amount": 500, "name": "string", "email": "string", "external_id": "string", "description": "string", "payin_method_name": "string", "payin_method_params": {}, "webhook_notification": { "endpoint_url": "https://example.org", "authorization_header": "SECRET" }, "expired_at": "string" }