error in return statements ----> Candle()

[Arfaz123]

class Candle {
final bool complete;
final int value;
final String time;
final CandleItem candleItem;

Candle({required this.complete, required this.value, required this.time, required this.candleItem});

factory Candle.fromJson(dynamic json) {
if (json == null) {
return Candle();
}

return Candle(
  complete: json['complete'],
  value: json['value'],
  time: json['time'],
  candleItem: CandleItem.fromJson(json['ask']),
);

}
}