Flutter problem on create model with Dio and Retrofit

I am using Dio and retrofit to make Http requests and I have a problem with the model that the API returns.

Previously I was using Flutter's own Http and parsing the response to fit what I needed.

The model I have is the following:

import 'package:json_annotation/json_annotation.dart';

part 'price_model.g.dart';

@JsonSerializable()
class PriceModel {
 String? date;
 String? hour;
 bool? isCheap;
 bool? isUnderAvg;
 String? market;
 double? price;
 String? units;

 PriceModel(
  {this.date,
  this.hour,
  this.isCheap,
  this.isUnderAvg,
  this.market,
  this.price,
  this.units});

 factory PriceModel.fromJson(Map<String, dynamic> json) => _$PriceModelFromJson(json);

 Map<String, dynamic> toJson() => _$PriceModelToJson(this);
}

My Retrofit class is as follows:

import 'package:electricity_price/app/home/models/price_model.dart';
import 'dart:async';
import 'package:dio/dio.dart';
import 'package:retrofit/http.dart';

part "price_repository.g.dart";

@RestApi()
abstract class PriceRepository {

 factory PriceRepository(Dio dio, {String baseUrl}) = _PriceRepository;

 @GET('all?zone=PCB')
 Future<List<PriceModel>> getPrices();
}

But the API response comes in this format:

{
 "00-01": {
   "date": "22-09-2022",
   "hour": "00-01",
   "is-cheap": true,
   "is-under-avg": true,
   "market": "PVPC",
   "price": 357.04,
   "units": "€/Mwh"
},
 "01-02": {
  "date": "22-09-2022",
  "hour": "01-02",
  "is-cheap": false,
  "is-under-avg": true,
  "market": "PVPC",
  "price": 377.26,
  "units": "€/Mwh"
}

The result of this is the following error:

DioError [DioErrorType.other]: type '_InternalLinkedHashMap<String, dynamic>' is not a subtype of type 'List?' in type cast

How can I model this or what else can I do to be able to parse the response?

Thanks in advance