There was laundry inside the drum when the washer-dryer was switched off. This has shifted the zero point.
Reset the zero point; see operating instructions.
To avoid shifting the zero point in future:
Switch on the washer-dryer before filling the drum.
Switch on the washer-dryer before emptying the drum.
Completely empty the drum at the end of the programme.
Do not add water via the detergent drawer.
