I am playing off a handicap of about 17. I have some 30 scores in the system (all counting towards the Garmin handicap). According to the Garmin connect app, my average 9-hole score for Garmin is 11 and average for 18 holes is 21.
At the same time, my Garmin handicap is 26.8. This is as high as my worst round I played (in the last 20 rounds).
Somewhere, somehow, a setting must be wrong. Anyone any idea what could be the problem? Could the slope rating posted for my course "Leeuwenbergh" be off (it should be 70.8/128)?