Settings Do Not Work

[joekamprad]

Settings crashes when opening

[phoenixcharm@phoenixcharm ~]$ gnome-control-center (gnome-control-center:6356): cc-wwan-panel-WARNING **: 21:59:49.321: Error connecting to ModemManager: Error calling StartServiceByName for org.freedesktop.ModemManager1: Unit dbus-org.freedesktop.ModemManager1.service not found. (gnome-control-center:6356): GLib-GIO-ERROR **: 21:59:49.353: Settings schema 'org.gnome.shell.app-switcher' is not installed Trace/breakpoint trap (core dumped)