Une exception non gérée s'est produite lors du traitement de la demande - ASP .NET Core

Je suis nouveau sur le noyau ASP .net. Cela me donne une erreur d'injection de dépendance comme:

InvalidOperationException: impossible de résoudre le service pour le type «Spinit.Data.Services.Repository.GameRepository» lors de la tentative d'activation de «SpinIt.Web.Controllers.CartController». Microsoft.Extensions.DependencyInjection.ActivatorUtilities.GetService (IServiceProvider sp, Type type, Type requiredBy, bool isDefaultParameterRequired)

StackTrace est ci-dessous:

Microsoft.Extensions.DependencyInjection.ActivatorUtilities.GetService(IServiceProvider sp, Type type, Type requiredBy, bool isDefaultParameterRequired)
lambda_method(Closure , IServiceProvider , object[] )
Microsoft.AspNetCore.Mvc.Controllers.ControllerActivatorProvider+<>c__DisplayClass4_0.<CreateActivator>b__0(ControllerContext controllerContext)
Microsoft.AspNetCore.Mvc.Controllers.ControllerFactoryProvider+<>c__DisplayClass5_0.<CreateControllerFactory>g__CreateController|0(ControllerContext controllerContext)
Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Next(ref State next, ref Scope scope, ref object state, ref bool isCompleted)
Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.InvokeInnerFilterAsync()
Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.InvokeNextResourceFilter()
Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.Rethrow(ResourceExecutedContext context)
Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.Next(ref State next, ref Scope scope, ref object state, ref bool isCompleted)
Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.InvokeFilterPipelineAsync()
Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.InvokeAsync()
Microsoft.AspNetCore.Builder.RouterMiddleware.Invoke(HttpContext httpContext)
Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)
Microsoft.AspNetCore.Session.SessionMiddleware.Invoke(HttpContext context)
Microsoft.AspNetCore.Session.SessionMiddleware.Invoke(HttpContext context)
Microsoft.AspNetCore.StaticFiles.StaticFileMiddleware.Invoke(HttpContext context)
Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore.MigrationsEndPointMiddleware.Invoke(HttpContext context)
Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore.DatabaseErrorPageMiddleware.Invoke(HttpContext httpContext)
Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore.DatabaseErrorPageMiddleware.Invoke(HttpContext httpContext)
Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)

Code CartController

public class CartController:Controller
{
    private readonly GameRepository _gameRepository;
    private readonly Cart _cartRepository;

    public CartController(GameRepository gameRepository, Cart cartRepository)
    {
        _gameRepository = gameRepository;
        _cartRepository = cartRepository;
    }

    public ViewResult Index()
    {
        var items = _cartRepository.GetCartItems();
        _cartRepository.CartItems = items;

        var sCVM = new CartViewModel
        {
            Cart = _cartRepository,
            CartTotal = _cartRepository.GetCartTotal()
        };
        return View(sCVM);
    }
}

J'ai également ajouté un service à Startup.cs

services.AddScoped<IGame, GameRepository>();
services.AddScoped<ICartItem, CartItemRepository>();