Question about Medela Freestyle Hands-free Electric Double Breast Pump

Medela recommends pressing and holding the On/Off button for 7/10 seconds until a sound is emitted in the event of charging or display problems. If nothing happens: Connect the charger → press and hold On/Off until a signal sounds, then release.
Otherwise, you can also open the rear cover (screw), remove the battery and then plug it back in after approx. 10 seconds. The charge indicator ("bAtt") can be reset with the reconnection.