I started using Ad Agency Pro with JA Healthcare template (i'm specifing the template because i do not know if errors depends on template) and in campaigns page, all dropdown menus appear on the bottom-left corner of the page.
To make everuthing work, i modified adagencycampaigns/tmpl/default.php adding to all
<ul class="dropdown-menu">
<li>
<a class="dropdown-item">
moreover, custom.css needs the following: .dropdown-menu {top: inherit !important; left:inherit !important;}
Another problem is about icons. Font family (in css) should be fontawesome and not Font Awesome 5 Free
Joomla 5.2.2