Password not updated...?

See more:

C#

ASP.NET

(Stored Procedure (ManageMember))

if @Check ='u' begin
	update Member

	set Password = @Password, Name = @Name, Email = @Email, Phone = @Phone, 
        Company = @Company, Gender = @Gender, BirthDate = @BirthDate,
        Question = @Question, Answer = @Answer

	where (UserName = @Username)
	end

----------------------------------------------------------------------------
(MainTable.cs)

public bool Update()
    {
        return LoadPropertiesToList("u");
    }

----------------------------------------------------------------------------
(Member.cs)

protected override bool LoadPropertiesToList(string TypeOfOperation)
    {
        SortedList SL = new SortedList();
        SL.Add("@Check", TypeOfOperation);
        SL.Add("@Username", Username);
        SL.Add("@Password", Password);
        SL.Add("@Name", Name);
        SL.Add("@Email", Email);
        SL.Add("@Phone", Phone);
        SL.Add("@Company", Company);
        SL.Add("@Gender", Gender);
        SL.Add("@BirthDate", BirthDate);
        SL.Add("@Question", Question);
        SL.Add("@Answer", Answer);
        ProcedureName = "ManageMember";
        
        if (db.RunProcedure(ProcedureName, SL) == 1)
            return true;
        else
            return false;
    }

------------------------------------------------------------------------------
(Utility.cs)

public static string ReadFromCookie(string CookieName,string Key,HttpRequest req)
{
    try
    {
        return req.Cookies[CookieName][Key].ToString();
    }
    catch
    {
        return null;
    }
}

---------------------------------------------------------------------------
(wucLogin.ascx.cs)

protected void Page_Load(object sender, EventArgs e)
{
string User = Utility.ReadFromCookie("Login","Username", Request);

if (User != null)
{
Redirect(User);
}
}

----------------------------------------------------------------------------------
(wucChangePassword.ascx.cs)

{
Member M = new Member();
static string User;

protected void Page_Load(object sender, EventArgs e)
{
User = Utility.ReadFromCookie("Login", "Username", Request);
lblUser.Text = User;
}
protected void btnChange_Click(object sender, EventArgs e)
{
User = Utility.ReadFromCookie("Login", "Username", Request);

if (txtNewPass.Text != txtRePass.Text)
lblMsgPass.Text = "The Password and Confirm Password is not the same";
else
{
if (M.ChangePassword(User, txtNewPass.Text))
lblMsgPass.Text = "Password Changed Successfuly";
else
lblMsgPass.Text = "Something Error";
}
}
}

What I have tried:

public bool ChangePassword(string Username, string NewPassword)
    {
        ????????????????????????????????
    }