Problem with my controller when using dapper on Asp.Net Core identity.

my user model

    public class User : IdentityUser
    {

    }

my userStore

public class UserStore : IUserStore<User>
    {
        private readonly string connectionString;

        public UserStore()
        {
            IConfiguration configuration = null;
            connectionString = configuration.GetValue<string>("DBInfo:ConnectionString");
        }

        public void Dispose()
        { }


        public async Task<IdentityResult> CreateAsync(User user, CancellationToken cancellationToken = default(CancellationToken))
        {
            using (SqlConnection conn = new SqlConnection(connectionString))
            {
                if (user == null)
                    throw new ArgumentNullException("user");

                using (SqlConnection connection = new SqlConnection(connectionString))
                {
                    await connection.ExecuteAsync("INSERT INTO Users(Id,UserName,Nickname,PasswordHash,SecurityStamp,IsConfirmed,ConfirmationToken,CreatedDate) VALUES(@Id,@UserName,@Nickname,@PasswordHash,@SecurityStamp,@IsConfirmed,@ConfirmationToken,@CreatedDate)", user);
                }
                return IdentityResult.Success;
            }
        }
        public Task<string> GetUserIdAsync(User user, CancellationToken cancellationToken = default(CancellationToken))
        {
            return Task.FromResult<string>(user.Id);
        }

        public Task<string> GetUserNameAsync(User user, CancellationToken cancellationToken = default(CancellationToken))
        {
            return Task.FromResult<string>(user.UserName);
        }

        public async Task<IdentityResult> UpdateAsync(User user, CancellationToken cancellationToken = default(CancellationToken))
        {
         if (user == null)
                    throw new ArgumentNullException("user");
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                await connection.ExecuteAsync("UPDATE Users SET UserName = @userName, PasswordHash = @passwordHash, SecurityStamp = @securityStamp WHERE UserId = @userId",
                    user);
            }
            return IdentityResult.Success;
        }

        public async Task<IdentityResult> DeleteAsync(User user, CancellationToken cancellationToken = default(CancellationToken))
        {
            if (user == null)
                throw new ArgumentNullException("user");
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                await connection.ExecuteAsync("DELETE FROM Users WHERE UserId = @userId", user);
            }
            return IdentityResult.Success;
        }

        public async Task<User> FindByIdAsync(string userId, CancellationToken cancellationToken = default(CancellationToken))
        {
            if (string.IsNullOrWhiteSpace(userId))
                throw new ArgumentNullException("userId");

            Guid parsedUserId;
            if (!Guid.TryParse(userId, out parsedUserId))
                throw new ArgumentOutOfRangeException("userId", string.Format("'{0}' is not a valid GUID.", new { userId }));
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                var user = await connection.QueryAsync<User>("SELECT * FROM Users WHERE Id = @Id", new {userId = parsedUserId});
                return user.SingleOrDefault();
                //connection.Query<User>("select * from Users where UserId = @userId", new { userId = parsedUserId }).SingleOrDefault();
            }
        }

        public async Task<User> FindByNameAsync(string normalizedUserName, CancellationToken cancellationToken = default(CancellationToken))
        {
            if (string.IsNullOrWhiteSpace(normalizedUserName))
                throw new ArgumentNullException("userName");
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                var user =
                    await connection.QueryAsync<User>("SELECT * FROM Users WHERE lower(UserName) = lower(@userName)",
                        new {normalizedUserName});
                return user.FirstOrDefault();
            }
        }
}

And the problem is here. In my controller, when trying to use UserManager it says has 9 parameters...but is this an core.identity model, because in asp.identity it doesn't need all arguments.

        public LoginController()
            : this(new UserManager<User>(new UserStore()))
        {
        }

        public LoginController(UserManager<User> userManager)
        {
            this.userManager = userManager;
        }

        public UserManager<User> UserManager { get; private set; }

thanx