If the PIN cannot be entered, the display is blocked or it cannot be switched off, you should try a cold start.
Cold start 1: Press the ON/OFF button under the top tube for approx. 15 seconds. The Stromer is switched off abruptly without shutting down. Press the button again to start the Stromer.
Cold start 2: This only works on models with a mechanical battery compartment lock. Remove the battery during operation - wait briefly - insert the battery - start the Stromer - run through the starting process.