Comment 2 for bug 1615270

Some progress has been made. As of now, if you restart (or otherwise kill appcenter) the issue will correct itself.

Jeremy seems to think that it might not be possible to solve under current packagekit API and it might be an upstream issue. He cites that it may possibly be related to https://bugs.launchpad.net/ubuntu/+source/gnome-software/+bug/1563155