I have a problem with my MXkeys. All of the function buttons are working fine except for the ones that control monitor brightness. They worked for the first time but since then they don't. Also, when I open the logi options+ app, I canť access my keyboard, it just shows "downloading" nonstop. Reconnecting the keyboard didn't work and I don't want to reinstall the app because I don't want to lose my MX Master 3 settings. Any help?