ViewContext.RouteData.Values["Controller"] always Null - Asp.Net Core 2.1

I started with the standard ASP.NET Core Web Application template using Asp.Net Core 2.1 as a starting point.

Then i added a left Navigation Panel in the shared folder like this: ActiveRouteTagHelper

In this Navigation Panel I want to highlight the active link and i used the following solution: Ben Cull's ActiveRouteTagHelper for MVC .

And then i encountered the following issue:

When i hit debug and the application starts i expect to see the a controller value in ViewContext.RouteData.Values["Controller"].

For the first and every other click even though one can see that the Url displays the the correct action and controller name

    private bool ShouldBeActive()
    {
        try
        {
            var currentController = ViewContext.RouteData.Values["Controller"].ToString();
            var currentAction = ViewContext.RouteData.Values["Action"].ToString();


        }
        catch (Exception ex)
        {
            return false;
        }
    }

I have removed the rest of the method for clarity.

My Startup Class:

        public void ConfigureServices(IServiceCollection services)
    {
        services.Configure<AppSettings>(_configuration);
        services.Configure<AppSettings>(_configuration.GetSection("PortalSettings"));
        var settings = _configuration.Get<AppSettings>();

        services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
        services.AddMvc();
        services.AddMvc().AddControllersAsServices();
        services.TryAddSingleton<IHttpContextAccessor, HttpContextAccessor>();
    }

    public void Configure(IApplicationBuilder app, IHostingEnvironment env)
    {
        if (env.IsDevelopment())
        {
            // If this is the case then enable more detailed error output
            app.UseDeveloperExceptionPage();

            // Display a more specific error page when an exception occurs connecting to the database
            app.UseDatabaseErrorPage();
        }
        else
        {
            // If this is not the case then forward the error to our generic view
            app.UseExceptionHandler("/Shared/Error");
            app.UseHsts();
        }

        app.UseHttpsRedirection();
        app.UseStaticFiles();

        app.UseMvc(routes =>
        {
            routes.MapRoute("default", "{controller}/{action}/{id?}");
        });
        app.UseAuthentication();
    }

My question is this, how do I get it that these two lines return a value? As no matter what I have tried has proved successful. The outcome is always null!!

var currentController = ViewContext.RouteData.Values["Controller"].ToString();
var currentAction = ViewContext.RouteData.Values["Action"].ToString();

Debug view

I have tried various routing mapping options, yet to no avail. Any ideas?