How can I fix my zanussi zwd12270w washing machine?

It stops mid cycle (water still in drum). Sometimes if you turn off and on again it will drain (on drain prog), then if leave for a while will work normally. Did the same thing couple of days ago, managed to drain (after a few goes of turning off and on, clicking as if starting but then stopping, eventually draining though). Tried wash cycle again this morning, stopped mid cycle again, won't drain either so water still in drum. For a few weeks it has sometimes had problems starting a wash cycle too, clicking on as if starting, but then stops after a few seconds. Pleeeeeease help!!!