Can't delete or edit bottom set of widgets in Today View
I am trying to delete some widgets from Today View on my iPad running iPadOS 15. When I long-press in a vacant space or press "edit", the top six widgets jiggle and show a minus sign, as they should, permitting me to delete them. But below this group of widgets, none of them jiggle or show a minus sign — and long-pressing on them does nothing either.
I tried deleting the underlying app for one of them, and even that does not delete the widget. It just produces an "unable to load" message on the widget.
Is this a bug, or am I missing something? Any remedy?
iPad Pro, iPadOS 15