Can NOT save plugin setting

I can NOT save the plugin settings. It gives me an error [object Object] when I hit save changes.

The error pops up for a few seconds next to the save changes button.

I was trying to change my options in the Plugin Settings.

On another note, I can’t seem to be able to perform a clean install. Does anyone know how to do a clean install? Every time I uninstall and reinstall, it still has my old API key stored.