Improving the algorithm
The planner schedules in the consumption of your appliance based on a big database containing consumption of different types and brands of Washing Machines, Dishwashers, Clothes Dryers etc..
A Washing Machine however has different types of programs and cycles for different types of clothes making it near impossible to determine the consumption for each and every appliance.
You can help improving the planner algorithm by adding a Submeter using either a Smappee Switch (Genius Only) or CT that measures the consumption of the appliance.
To link the submeter, go to the details of the appliance (Control -> Smart Devices -> Name of your appliance"), search for and press the "Add measurement" button.