WEB API, .NET CORE, C#, NET 8.0, SERILOG, SINK FILE, SERILOG EXPRESSIONS

Good morning,
as per demo attached here (https://github.com/serilog/serilog-sinks-file/issues/317) I have some problem to write logs filtering by a certain Context by using the appsettings.json
It write everything with every types of context.

ex.Controller API

       `Log.ForContext("logtype", "pippo").Information("This is a pippo log");`

THIS IS THE EXAMPLE THAT DOESN’T WORK
Program.cs

       `var configuration = new ConfigurationBuilder().SetBasePath(Directory.GetCurrentDirectory())
       .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true).Build();
       
       // Configura Serilog utilizzando la configurazione
        Log.Logger = new LoggerConfiguration()
            .ReadFrom.Configuration(configuration)
            .CreateLogger();`

appsettings.json

       `"Serilog": {
         "Using": [ "Serilog.Sinks.Console", "Serilog.Sinks.File", "Serilog.Expressions" ],                       //"Serilog.Filters.Expressions",
         "MinimumLevel": "Debug",
         "Enrich": [ "FromLogContext" ],
         "WriteTo": [
           //{ "Name": "Console" },
           {
             "Name": "File",
             "Args": {
               "path": "logs/log.txt",
               "rollingInterval": "Day",
               "outputTemplate": "{Timestamp:yyyy-MM-dd HH:mm:ss.fff}Z - {Properties:j}            
           {SourceContext} {Level:u3} {Message:lj}{NewLine}{Exception}"         
             },
             "Filter": [
               {
                 "Name": "ByIncludingOnly",
                 "Args": {
                   //"expression": "Contains(@p['logtype'],'pippo')"
                   //"expression": "@p['logtype'] is null"
                   //"expression": "(@Properties['logtype'] == 'pippo')"
                   "expression": "Contains(@Properties['logtype'], 'pippo')"
                   //"expression": "Equals(@Properties['logtype'], 'pippo')"
                   //"expression": "logtype='pippo'"
                 }
               }
             ]
           }
         ]
       }`

BUT if I configure serilog in the Program.cs without the appsettings.json it works
THIS EXAMPLE WORKS

       ` Log.Logger = new LoggerConfiguration()
        .Enrich.FromLogContext()
        .MinimumLevel.Debug()
        .WriteTo.Console()
        .WriteTo.Logger(lc => lc
        .Filter.ByIncludingOnly(Matching.WithProperty<string>("logtype", p => p == "pippo"))
        .WriteTo.File("logs/log.txt", rollingInterval: RollingInterval.Day,
         outputTemplate: "{Timestamp:yyyy-MM-dd HH:mm:ss.fff}Z - {Properties:j} {SourceContext} {Level:u3} {Message:lj}{NewLine}{Exception}"))
        .CreateLogger();
        builder.Host.UseSerilog();`