Can't reinstall LASTfm plugin

I couldn’t get scrobbling working so I tried to uninstall and reinstall the plugin and it wouldn’t uninstall via the gui, failed with an error, now it won’t install again I get this message:

Downloading plugin at
Creating install location
Unpacking plugin
An error occurred while installing the plugin Error: Plugin lastfm already exists

I searched the entire install with find and grep and cannot find plugin stuff at all, I deleted anything I could find hoping it’d allow me to reinstall it, it did not. any ideas?