function plt_hide_mailin_menus() {
//Hide the "Brevo" menu.
remove_menu_page('sib_page_home');
//Hide the "Brevo → Home" menu.
remove_submenu_page('sib_page_home', 'sib_page_home');
//Hide the "Brevo → Forms" menu.
remove_submenu_page('sib_page_home', 'sib_page_form');
}
add_action('admin_menu', 'plt_hide_mailin_menus', 10000);