If you're on a K "light fare", you're out of luck. In my experience, they stopped allowing Senators (LX *G) on those fares to check bags for free. This even applies after an upgrade on miles or vouchers to business class.

If you on K "classic fare", you should get a free checked bag + 1 extra for being *G.

You can find out your baggage allowance by pulling up your booking on the Swiss website and have your e-ticket send to your email id. It will include these details.