我實作了一個class繼承ValidationAttribute,做一個客製化驗證,我碰到的問題是我很確定有進入觸發錯誤的scope ,有正確return ValidationResult,但是 error message 沒有顯示在view上,想請問各位大大堤點我一下

-----客製化驗證的class code------------------------------
public class Check_acccountAttribute : ValidationAttribute
{
private test_shoppingEntities db = new test_shoppingEntities();

    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
        int? check_account_unique = db.Database.SqlQuery<int>("Select Count(Account) from Customer  Where Account=@AccountStr", new SqlParameter("AccountStr", value.ToString())).FirstOrDefault();
        
        if ((check_account_unique > 0)&&(value != null))
        {
         Debug.WriteLine(check_account_unique+"ggg");

         return new ValidationResult("會員帳號重複", new[] { "Account" });
        }
        else
        {
            return ValidationResult.Success;
        }
      
    }

}
--------------------------model code 只留下客製化驗證欄位code------------

[MetadataType(typeof(PartialCustomer))]
public partial class Customer
{

}
public class PartialCustomer
{
    [Display(Name = "會員帳號")]
    [Required(ErrorMessage = "Account必須輸入")]
    [Check_acccount(ErrorMessage = "會員帳號重複")]
    public string Account { get; set; }   
}

-----------------controller action---------------------------
if ((ModelState.IsValid))
{
Debug.WriteLine("ModelState.IsValid1");
customer.CustomerId = "default";
db.Customer.Add(customer);

            try
            {
                Debug.WriteLine("22222");
                db.SaveChanges();
                ModelState.Clear();
                return JavaScript("alert('註冊會員成功!!!!');");
            }
            catch (Exception ex)
            {
                throw;
            }      
        }   
        return View(customer);

**-------------view--------------------------------------------- **

      @Html.EditorFor(model => model.Account, new { htmlAttributes = new { @class = "form-control", style = "width: 150px;height:50px;font-size:18px;" } })<br />
      
      @Html.ValidationMessageFor(model => model.Account,"", htmlAttributes: new { @class = "", style = "font-size:18px; font-weight:bold;color:	#FF4500;" })<br />

      <label style="color:lightyellow;font-weight:bold;font-size:20px;">PassWord</label><br />
      
       @Html.EditorFor(model => model.Password, new { htmlAttributes = new { @class = "form-control", style = "width: 150px;height:50px;font-size:18px;" } }) <br />
                        
       @Html.ValidationMessageFor(model => model.Password, "", htmlAttributes: new { @class = "", style = "font-size:18px; font-weight:bold;color:	#FF4500;" })<br />
                        
        <input type="submit" value="註冊" class="btn btn-primary" style="margin-top:10px;width: 150px;height:50px;font-size:25px;" />
                    </div>

        <div class="col-md-8 col-lg-8 col-sm-8">
         @Html.ValidationSummary(true, "", htmlAttributes: new { @class = "", style = "font-size:18px; font-weight:bold;color:	#FF4500;" })
   </div>