Change the menu order in Product Details >> Action >> Sidebar

[AndyW]

I am trying to order menu items in Product Details >> Action >> Sidebar with the following code, but it does not seem to work

add_hook('ClientAreaPrimarySidebar', 1, function (MenuItem $primarySidebar) {
    if (!is_null($primarySidebar->getChild('Service Details Actions')) && !is_null($primarySidebar->getChild('Service Details Actions')->getChild('client_retrieve_certificate'))) {
       $secondarySidebar->getChild('client_retrieve_certificate')
       ->setOrder(100)   
}};

What am I missing here?