Its a problem recently I am facing in my recent project.
So my client told me you should clear previous history in every textbox. So I just write a textbox properties in Page_Prerender event in my page(codebehind).
protected void Page_PreRender(Object sender, EventArgs e)
{
txtPassword.Attributes.Add(“autocomplete”, “off”)
txtConfirmPassword.Attributes.Add(“autocomplete”, “off”);
}
It will solve your problem.