How can I develop multiple widgets for a WordPress theme?
When registering a sidebar, you can use certain placeholders for the widget classes. Here’s an example taken from the codex: ‘before_widget’ => ‘<li id=”%1$s” class=”widget %2$s”>’, It’s the lack of %1$s and %2$s that is causing your issues. When in doubt always read the documentation on the codex and the developer hub/handbooks