Not possible to add sidebar???

Hi i cant add a sidebar and make it work, i added to the header but when i call it i only get the “sidebar-1” widgets, i mean, all the widgets of sidebar-1 moves from the sidebar zone to the place where i’m calling the new sidebar (with <?php get_sidebar( 'mynewsidebar' ); ?>)
ive tried with the default sidebar register method in functions.php, and with “args” method, but get the same result
tks if could help