save response of http flutter

I made a model in which I go to get the various data, they are all ok except the 'card' in which I cannot save the data to its inside in my Model .. how can I save the data inside the 'card' of the Map you see in the picture?

    factory VoucherPdf.fromJson(Map<String, dynamic> json) {
    try {
      return VoucherPdf._(
        id: json.get('id') as int,
        orderId: json.get('order_id') as int,
        quoteId: json.get('quote_id') as int,
        createdAt: json['createdAt'] == null
            ? null
            : DateTime.parse(json.get('createdAt') as String),
        status: json.get('status') as int,
        card: json.get('card') as Map<String, dynamic>,
      );
    } catch (e) {
      logger.e('[VoucherPdf-fromJson] Deserializing error: ${e.oneline}');
      rethrow;
    }
  }