Error RZ10012 when adding a component in blazor

Hello,

I'm trying to learn Blazor with a youtube video. I have this page :

• MainLayout.razor

@inherits LayoutComponentBase

<div class="page">
    <div class="sidebar">
        <NavMenu />
    </div>

    <main>
        <div class="top-row px-4">
            <CartMenu /> //Error RZ10012 here
        </div>

        <article class="content px-4">
            @Body
        </article>
    </main>
</div>

the CartMenu isn't shown on the page and I've got a green error RZ10012 (On the net, It's said that is introduced with the new version of VS... (I use VS2022 Community))

• CartMenu.razor

@implements IDisposable
@inject IShoppingCartService shoppingCartService

<a href="ShoppingCart" class="btn btn-info">
    <i class="oi oi-cart"></i>&nbsp;Cart
    <span class="badge bg-black">@shoppingCartItemsCount</span>
</a>

@code{
    private int shoppingCartItemsCount = 0;

    protected override void OnInitialized()
    {
        shoppingCartService.OnShoppingCartChanged += ShoppingCartChanged;
    }

    protected void ShoppingCartChanged(int totalQty)
    {
        shoppingCartItemsCount = totalQty;
        StateHasChanged();
    }

    void IDisposable.Dispose()
    {
        shoppingCartService.OnShoppingCartChanged -= ShoppingCartChanged;
    }
}

Here, there is an error on IShoppingCartService referencing

• _Imports.razor

@using System.Net.Http
@using System.Net.Http.Json
@using Microsoft.AspNetCore.Components.Forms
@using Microsoft.AspNetCore.Components.Web
@using Microsoft.AspNetCore.Components.Web.Virtualization
@using Microsoft.AspNetCore.Components.WebAssembly.Http
@using Microsoft.JSInterop
@using ShopOnline.Web
@using ShopOnline.Web.Shared
@using ShopOnline.Models.Dtos
@using ShopOnline.Web.Services.Contracts

• IShoppingCartService.cs

using ShopOnline.Models.Dtos;

namespace ShopOnline.Web.Services.Contracts
{
    public interface IShoppingCartService
    {
        Task<List<CartItemDto>> GetItems(int userId);
        Task<CartItemDto> AddItem(CartItemToAddDto cartItemToAddDto);
        Task<CartItemDto> DeleteItem(int id);
        Task<CartItemDto> UpdateQty(CartItemQtyUpdateDto cartItemQtyUpdateDto);

        event Action<int> OnShoppingCartChanged;
        void RaiseEventOnShoppingCartChanged(int totalQty);
    }
}

• ShoppingCartService.cs

using Newtonsoft.Json;
using ShopOnline.Models.Dtos;
using ShopOnline.Web.Services.Contracts;
using System.Net.Http.Json;
using System.Text;

namespace ShopOnline.Web.Services
{
    public class ShoppingCartService : IShoppingCartService
    {
        private readonly HttpClient httpClient;

        public ShoppingCartService(HttpClient httpClient)
        {
            this.httpClient = httpClient;
        }

        public event Action<int> OnShoppingCartChanged;

        public async Task<CartItemDto> AddItem(CartItemToAddDto cartItemToAddDto)
        {
            try
            {
                var response = await httpClient.PostAsJsonAsync<CartItemToAddDto>("api/ShoppingCart", cartItemToAddDto);
                if (response.IsSuccessStatusCode)
                {
                    if (response.StatusCode == System.Net.HttpStatusCode.NoContent)
                        return default(CartItemDto);

                    return await response.Content.ReadFromJsonAsync<CartItemDto>();
                }
                else
                {
                    var message = await response.Content.ReadAsStringAsync();
                    throw new Exception($"Http status code:{response.StatusCode} Message: {message}");
                }
            }
            catch (Exception)
            {

                throw;
            }
        }

        public async Task<CartItemDto> DeleteItem(int id)
        {
            try
            {
                var response = await httpClient.DeleteAsync($"api/ShoppingCart/{id}");
                if (response.IsSuccessStatusCode)
                    return await response.Content.ReadFromJsonAsync<CartItemDto>();

                return default(CartItemDto);

            }
            catch (Exception)
            {
                //Log exception
                throw;
            }
        }

        public async Task<List<CartItemDto>> GetItems(int userId)
        {
            try
            {
                var response = await httpClient.GetAsync($"api/ShoppingCart/{userId}/GetItems");
                if (response.IsSuccessStatusCode)
                {
                    if (response.StatusCode == System.Net.HttpStatusCode.NoContent)
                    {
                        return Enumerable.Empty<CartItemDto>().ToList();
                    }
                    return await response.Content.ReadFromJsonAsync<List<CartItemDto>>();
                }
                else
                {
                    var message = await response.Content.ReadAsStringAsync();
                    throw new Exception($"Http status code:{response.StatusCode} Message: {message}");
                }
            }
            catch (Exception)
            {

                throw;
            }
        }

        public void RaiseEventOnShoppingCartChanged(int totalQty)
        {
            if (OnShoppingCartChanged != null)
                OnShoppingCartChanged.Invoke(totalQty);
        }

        public async Task<CartItemDto> UpdateQty(CartItemQtyUpdateDto cartItemQtyUpdateDto)
        {
            try
            {
                var jsonRequest = JsonConvert.SerializeObject(cartItemQtyUpdateDto);
                var content = new StringContent(jsonRequest, Encoding.UTF8, "application/json-patch+json");
                var response = await httpClient.PatchAsync($"api/ShoppingCart/{cartItemQtyUpdateDto.CartItemId}", content);

                if (response.IsSuccessStatusCode)
                    return await response.Content.ReadFromJsonAsync<CartItemDto>();

                return null;
            }
            catch (Exception)
            {
                //Log exception
                throw;
            }
        }
    }
}

I asked th question to the author, but he doesn't answer...

Some has a solution ?

thanks in advance

Regards.