Asp.net – An error occured after adding the initial Migration while accessing the Microsoft.extension.hosting services

Once I have added my first Migration Add-Migration InitialMigration, it display this error below,

An error occurred while accessing the Microsoft.Extensions.Hosting services. Continuing without the application service provider. Error: Failed to load configuration from file ‘C:UsersAmmadsourcereposEmployeesProjectEmployeesProjectappsettings.json’.
Unable to create a ‘DbContext’ of type ‘ApplicationDbContext’. The exception ‘Unable to resolve service for type ‘Microsoft.EntityFrameworkCore.DbContextOptions`1[EmployeesProject.Context.ApplicationDbContext]’ while attempting to activate ‘EmployeesProject.Context.ApplicationDbContext’.’ was thrown while attempting to create an instance. For the different patterns supported at design time, see https://go.microsoft.com/fwlink/?linkid=851728

Please let me know the solution as I need to add the first migration. thanks

Please find my code below for just one simple class created Employee.cs

namespace EmployeesProject.Models
{
    public class Employee
    {

        public int Id { get; set; }

        public string FirstName { get; set; }
        public string MiddleName { get; set; }

        public string LastName { get; set; }
        public string EmailAddress { get; set; }
        public int PhoneNumber { get; set; }
    }
}

My application db context class code is mentioned below

using EmployeesProject.Models;
using Microsoft.EntityFrameworkCore;

namespace EmployeesProject.Context
{
    public class ApplicationDbContext : DbContext
    {

        public ApplicationDbContext(DbContextOptions<ApplicationDbContext>contextOptions): base(contextOptions)
        {

        }

        // Code First Approach
        public DbSet<Employee> Employees { get; set; }
    }
}

The appsetting.json code is below

{

     "ConnectionStrings": {
        "DefaultConnection": "Server": "DESKTOP-DFBVCE0;Database:Employees; User Id={username};Password:{password}; TrueServerCertificate:True"
      },
    
      "Logging": {
        "LogLevel": {
          "Default": "Information",
          "Microsoft.AspNetCore": "Warning"
        }
      },
      "AllowedHosts": "*"
    }

Please find Program.cs below,

namespace Employeeproject
{
    public class Program
    {
        public static void Main(string[] args)
        {
            var builder = WebApplication.CreateBuilder(args);

            // Add services to the container.
            builder.Services.AddControllersWithViews();

            var app = builder.Build();

            // Configure the HTTP request pipeline.
            if (!app.Environment.IsDevelopment())
            {
                app.UseExceptionHandler("/Home/Error");
                // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
                app.UseHsts();
            }

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

            app.UseRouting();

            app.UseAuthorization();

            app.MapControllerRoute(
                name: "default",
                pattern: "{controller=Home}/{action=Index}/{id?}");

            app.Run();
        }
    }
}