How to update the datagrid after updating a selected value

Question

The Below code is updating the record but not reflecting it inside the Datagrid. What should I add to the update function to reflect the changes instantly after the update message?

Xaml Code

 <Button Command="{Binding CmdUpdateUser}" Content="Update User"/>

ViewModel File

         private void UpdateUser()
        {
            try
            {
                con = new SqlConnection(connectionString);
                con.Open();
                cmd = new SqlCommand($"UPDATE Customer " +
                    $"SET Id='{Id}',Name='{Name.ToString()}'," +
                    $"Age='{Age}',Country='{Country.ToString()}'," +
                    $"Active='{Convert.ToBoolean(Active)}'" +
                    $" WHERE Id='{Convert.ToInt32(SelectedCustomer.id)}'",con);
                int n=cmd.ExecuteNonQuery();
                if (n > 0)
                {                   
                    MessageBox.Show("Update Successful");                 
                }
                Customer current = customer.Where(x => x.id == SelectedCustomer.id).FirstOrDefault();
                current.id =Id;
                current.name =Name;
                current.age = Age;
                current.country = Country;
                current.active = Active;
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message.ToString());
            }
            finally
            {
                con.Close();
                
            }
        }

Answer 1

The Customer class should implement INotifyPropertyChanged and raise change notifications in the setters of the Id, Name, Age, Country and Active properties:

public class Customer : INotifyPropertyChanged
{
    private string _name;
    public string Name
    {
        get { return _name; }
        set { _name = value; OnPropertyChanged(); }
    }

    //+ the same for the rest of the properties

    public event PropertyChangedEventHandler PropertyChanged;
    protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null) =>
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));

}