Step 1:
The error may be due to the fiber screen or the pump housing being clogged.
Step 2:
The error may be due to the turbine (pump vane) on the drain pump not being able to turn. Test with your finger, a screwdriver or similar whether the mill can turn. If it cannot rotate, you should find out what is blocking the wing and remove it.
Step 3:
The error may be due to a clogged drain hose or drain.
Step 4:
The error may be due to a clogged bottom hose. The bottom hose is a large accordion hose between the sink and the pump. If there is water in the machine even though you have the mesh strainer out, it will be the bottom hose that is blocked.
If all the above points are in order, the error may be due to a defective pump. If the pump is faulty, you will often find that it does not empty the water out and there will therefore be water in the machine.