hoover washing machine won't stop filling!?

My Hoover Nextra HNK 6167 mega load 7.5kg fills up and won't stop. The machine will drain freely, spins and obviously fills! All the lights flashed when I turned it on again. As it fills, the water is leaking out of a clear plastic spout which tapers at the end (some sort of overflow?) running up from the large black drain hose which runs to the filter. The filter is clear and the machine drains freely. Any ideas?