string json = File.ReadAllText($"./assets/JSON/{mapName}.json");
Console.WriteLine(json);
var gridMapData = JsonConvert.DeserializeObject<GridMapData>(json);

Here im deserializing an object and for release mode it works normally. But when compiled natively (PublishAot) like below:

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net8.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
    <PublishAot>true</PublishAot>
    <InvariantGlobalization>true</InvariantGlobalization>
    <Platforms>AnyCPU;x64;x86</Platforms>
    <ApplicationManifest>app.manifest</ApplicationManifest>
    <AllowUnsafeBlocks>True</AllowUnsafeBlocks>
    <PublishAot>true</PublishAot> --> here 
  </PropertyGroup>

This error Newtonsoft.Json.JsonSerializationException: Unable to find a constructor.
start happening ( from the same json and same class type to desserialize it ). Also, i can see on the Console.WriteLine that the json string is correctly being showed.

Appreciate any help or feedback.

I tried to satisfy the error by changing the class.

public class GridMapData
{
    public int width;
    public int height;
    public Dictionary<string, int> cells;

    --> Things i tried
    //public GridMapData(int Width, int Height, Dictionary<string, int> Cells)
    //{
    //    this.width = Width;
    //    this.height = Height;
    //    this.cells = Cells;
    //}
    //public GridMapData() { }

    //[JsonConstructor]
    //public GridMapData() { }
}