Propertygrid user input data validation issue

Start with the supplied WPF reproduction at XctkPropertyGrid and PropertyGrid_Loaded, using the Person and Person2 examples. Trace how PropertyGrid handles IDataErrorInfo and DataAnnotations validation during editing and focus loss. No repository file or test is identified; done means invalid input shows appropriate feedback and the error state clears when the value becomes valid.

question1: [Range()] causes the UI to have no user error prompts
//test example as follow:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Runtime.CompilerServices;
namespace WpfApp1
{
public class Person: INotifyPropertyChanged, IDataErrorInfo
{
[Required(ErrorMessage = "Name is Required")]
[DisplayName("Name")]
public string Name { set; get; }

    [Range(0,150,ErrorMessage = "Age= 0~150")]
    [DisplayName("Age")]
    public int Age { set; get; }

    public event PropertyChangedEventHandler? PropertyChanged;

    [Browsable(false)]
    public string Error { get; }

    public  string this[string propertyName]
    {
        get
        {
            if (string.IsNullOrEmpty(propertyName))
            {
                throw new ArgumentException("Invalid property name", propertyName);
            }
            string error = string.Empty;
            var val = GetType().GetProperty(propertyName).GetValue(this, null);
          
            var results = new List<System.ComponentModel.DataAnnotations.ValidationResult>(1);
            var result = Validator.TryValidateProperty(val, new ValidationContext(this, null, null)
                { MemberName = propertyName }, results);
            if (!result)
            {
                var validationResult = results.First();
                error = validationResult.ErrorMessage;
            }
            
            return error;
        }
    }

    protected void RaisePropertyChanged([CallerMemberName] string propertyName = null) => this.OnPropertyChanged(new PropertyChangedEventArgs(propertyName));
   
    protected virtual void OnPropertyChanged(PropertyChangedEventArgs args)
    {
        PropertyChangedEventHandler propertyChanged = this.PropertyChanged;
        if (propertyChanged == null)
            return;
        propertyChanged((object)this, args);
    }
}

}

<xctk:PropertyGrid Name="XctkPropertyGrid" Loaded="PropertyGrid_Loaded"></xctk:PropertyGrid>

private void PropertyGrid_Loaded(object sender, RoutedEventArgs e)
{
Person p = new Person(){Age = 20,Name = "wala"};

        this.XctkPropertyGrid.SelectedObject = p;
    }

[Range (0150, ErrorMessage="Age=0-150")] can prevent users from entering illegal values, but there is no red box mark or error prompt. Debugging found that this [string propertyName] indexer has not been called because it prevents users from entering illegal values.

question2:use person2 insteadof person1,When the user inputs an incorrect value, a red boder will prompt, but when the user leaves the attribute input box, the value in the red boder will return to the legal value, but the red boder will not disappear.
public class Person2 : INotifyPropertyChanged, IDataErrorInfo
{

    [DisplayName("Name")]
    public string Name { set; get; }

    private int _age;
    [DisplayName("Age")]
    public int Age {
        set
        {
            if (!ValidataProperty(nameof(Age), value))
                return;
                _age = value;
            RaisePropertyChanged(nameof(Age));
        }
         get
        {
            return _age;
        }}

    public event PropertyChangedEventHandler? PropertyChanged;

    [Browsable(false)]
    public string Error { get; }

    protected bool ValidataProperty(string propertyName, object val)
    {

        if (propertyName.Equals(nameof(Age)))
        {
            int ageVal = (int)val;
            if (ageVal < 0 || ageVal > 150)
            {
                ErrorProperty = propertyName;
                ErrorMsg = "Age =0~150";
                return false;
            }
                
        }

        ErrorMsg = string.Empty;
        ErrorProperty = string.Empty;
        return true;
    }

    private string ErrorProperty;
    private string ErrorMsg;

    public string this[string propertyName]
    {
        get
        {
            if (ErrorProperty.Equals(propertyName))
            {
                return ErrorMsg;
            }

            return string.Empty;
        }
    }

    protected void RaisePropertyChanged([CallerMemberName] string propertyName = null) => this.OnPropertyChanged(new PropertyChangedEventArgs(propertyName));

    protected virtual void OnPropertyChanged(PropertyChangedEventArgs args)
    {
        PropertyChangedEventHandler propertyChanged = this.PropertyChanged;
        if (propertyChanged == null)
            return;
        propertyChanged((object)this, args);
    }
}