Troubles with Schlumpf Shifter button

[Fatlazypig]

Did a little search
There’s some ideas on this thread which may help

Slipping Schlumpf and short axle??

Anybody have similar problem and/or answers? I have a minimally used, on simple street riding, KH/Shlumpf hub on 36" uni that suddenly, while on a ride, began freewheeling in low gear It will not engage at all in low, but will in high. I now have it out of frame and without cranks and buttons which, it seems to me, eliminates any incorrect adjustment issues?..and it still freewheels in low. I never noticed before, but now see with curiosity, that the axle shaft on the side with the un-knurle…