Start by testing the water inlet valve to make sure it is stopping the flow when it should. Start filling the machine as normal. Then while water is flowing, open the lid or press the timer knob in to stop the machine. Water flow should stop immediately. If it hesitates more than a few seconds or does not stop flowing at all then the inlet valve is faulty and should be replaced. Repeat this several times to make sure. If inlet valve checks out ok then post back here and I will tell you what to check next. Most times it is the valve.
Linoln Appliance NZ, June 2013