Access Token URL = https://unsitio/web/token
Grant Type = password
Authorization Grants = password
Client Id = nnnnnnnn
Client Secret = [Vacio]
Scope = [Vacio]
Username = hhhhhh@vvvv.ggg.oooo.lll
Password = sssssssss

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)
{
    JwtSecurityTokenHandler.DefaultInboundClaimTypeMap.Clear();

    services.AddAuthentication(options =>
    {
        options.DefaultScheme = CookieAuthenticationDefaults.AuthenticationScheme;
        options.DefaultChallengeScheme = OpenIdConnectDefaults.AuthenticationScheme;
    })
    .AddCookie()
    .AddOpenIdConnect(options =>
    {
        options.SignInScheme = CookieAuthenticationDefaults.AuthenticationScheme;
        options.Authority = "https://api.comprobanteselectronicos.go.cr/recepcion/v1/&jsoncallback=?"; // Auth Server
        options.RequireHttpsMetadata = true; // only for development
        options.ClientId = "api-stag"; // client setup in Auth Server
        options.ClientSecret = "";
        options.ResponseType = "code id_token"; // means Hybrid flow
        options.Scope.Add("fiver_auth_api");
        options.Scope.Add("offline_access");
        options.GetClaimsFromUserInfoEndpoint = true;
        options.SaveTokens = true;
    });

    services.AddMvc();
}

public void Configure(IApplicationBuilder app,IHostingEnvironment env)
{
    app.UseAuthentication();
    app.UseMvcWithDefaultRoute();
}

[Authorize]
    public class HomeController : Controller
    {
        [AllowAnonymous]
        public IActionResult Index()
        {
            return View();
        }

        public async Task<IActionResult> Movies()
        {
            var accessToken = await HttpContext.GetTokenAsync("access_token");

            var client = new HttpClient();
            client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", accessToken);
            var content = await client.GetStringAsync("https://api.comprobanteselectronicos.go.cr/recepcion-sandbox/v1/&jsoncallback=?");

            var model = JsonConvert.DeserializeObject(content);

            return View(model);
        }

        public async Task Logout()
        {
            await HttpContext.SignOutAsync(CookieAuthenticationDefaults.AuthenticationScheme);
            await HttpContext.SignOutAsync(OpenIdConnectDefaults.AuthenticationScheme);
        }