using System;

using System.Text.Json;

using Newtonsoft.Json;

public class Program

{

    public static void Main()

    {

        //var text = "{\"Product\": \"TUwsZjV4x1MDq7W3tsEX2K\"}";

        //var s = JsonSerializer.Deserialize<MessageThread>(text);

        var q = new MessageThread{Product = Guid.NewGuid().ToString()};

        Console.WriteLine(q.Product);

        Console.WriteLine(JsonConvert.SerializeObject(q));

        Console.WriteLine(System.Text.Json.JsonSerializer.Serialize(q));

        //Console.WriteLine(s.Product);

    }

}

​

public class MessageThread

{

    public string Product;

}