There is a trap that will catch every new Experience Builder developer at some point, usually the first time they add a sidebar.
Here I have a Legend in a Sidebar that covers up about half my map area.
I open up the Preview mode and I start clicking my map. The popups work fine in the west, but as I move east. They suddenly stop working.
Why is this happening? Well, even though the sidebar is closed the Sidebar widget is still on top of the map and it is effectively blocking you from interacting with your map.
The fix is to rearrange your layout, so that the map is now in the always open side of the sidebar. Starting with my arrangement with the sidebar directly on top of the map:
