Unable to get Configuration object using validationContext

Question

I am working an API application, I am using ValidationAttribute class to write custom validator for my inputs.

I have encountered a situation where I need Configuration object to read some values from appsettings.json

So I am using Get Service method to get the Configuration using Validation Context. Below is the code I am using.

Now the problem is this code works fine with SimpleValidator1 and doesn't work in SimpleValidator2 both the classes have same code, but when I try to get the configuration object in SimpleValidator2 it returns null where as in SimpleValadator1 I am getting the object.

SimpleValidator2 is being used in one of the Object being dynamically assigned to SimpleInfo in Simple1 class.

I am not sure what's going wrong here, can anyone suggest any possible issue? Or is there any alternate way to access the appsettings in CustomValidator extending ValidationAttribute? Any help is highly appreciated, thanks in advance.

SimpleValidator1

 public class SimpleValidator1 : ValidationAttribute
{
    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
        if (value == null)
        {
            return ValidationResult.Success;
        }

        var configuration = GetConfiguration(validationContext);
        var masterDataPath = configuration.GetValue<string>("MasterDataPath");
        //some logic here
        return ValidationResult.Success;
    }

    public IConfiguration GetConfiguration(ValidationContext validationContext)
    {
        var configuration = (IConfiguration)validationContext
            .GetService(typeof(IConfiguration));

        return configuration;
    }
}

SimpleValidator2

public class SimpleValidator2 : ValidationAttribute
{
    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
        if (value == null)
        {
            return ValidationResult.Success;
        }

        var configuration = GetConfiguration(validationContext);
        var masterDataPath = configuration.GetValue<string>("MasterDataPath");
        //some logic here
        return ValidationResult.Success;
    }

    public IConfiguration GetConfiguration(ValidationContext validationContext)
    {
        var configuration = (IConfiguration)validationContext
            .GetService(typeof(IConfiguration));

        return configuration;
    }
}

Startup

public Startup(IConfiguration configuration)
    {
        Configuration = configuration;
    }

    public IConfiguration Configuration { get; }

    // This method gets called by the runtime. Use this method to add services to the container.
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddControllers();
        services.AddSwaggerGen(c =>
        {
            c.SwaggerDoc("v1", new OpenApiInfo
            {
                Title = "XX.API",
                Version = "v1"
            });
        });

        services.AddAutoMapper(typeof(Startup), typeof(AutoMapperProfile));
        services.AddSingleton(Configuration);
        services.AddHttpContextAccessor();
        InjectorConfig.Init(services);
    }

    // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        app.UseMiddleware<AuthMiddleware>();
        if (!env.IsEnvironment(Environments.PROD))
        {
            app.UseDeveloperExceptionPage();
            app.UseSwagger();
            app.UseSwaggerUI(c =>
            {
                c.SwaggerEndpoint("/swagger/v1/swagger.json", "XX.API v1");
                c.RoutePrefix = string.Empty;

            });
        }

        var serviceProvider = app.ApplicationServices;
        var globalAppLogger = serviceProvider.GetService<ILogger<GlobalAppLog>>();
        ConfigureExceptionHandler(app, globalAppLogger);

        app.UseHttpsRedirection();
        app.UseRouting();
        app.UseAuthorization();

        app.UseEndpoints(endpoints =>
        {
            endpoints.MapControllers();
        });
    }
}

Usage of validator in class

 public class Simple1
{
    [Required]
    [SimpleValidator1]
    public long SimpleOneId { get; set; }

    [Required]
    public dynamic SimpleInfo { get; set; } //Simple2 will be assigned to this dynamically 
}

public class Simple2 
{
    [Required]
    [SimpleValidator2]
    public long TypeCid { get; set; }
}