Why can't I turn off stupid distracting activity tracking on my Garmin 255?

Both the online and PDF owners manual for my Garmin 255 sports watch state that I can turn off Activity Tracking with a few simple clicks. But the option noted on the Garmin website is not available!  Now my watch randomly beeps when I climb a flight of stairs. This is stupid and distracting. And the watch counts my steps, which I hate and want to turn off.  I didn't buy the watch to track my daily non-sports movement. How can I turn it off, per published Garmin instructions?