Fisher and Paykel Smartdrive 051 won’t fill

My F&P smartdrive 051 gets part way through the rinse cycle then won’t fill. It sounds as if the water inlet solenoids are opening very briefly then closing again. This repeats a few times and then it stops, goes quiet & then starts a rhythmic beeping that will only stop if I turn it off. I can still spin the drum and agitator by hand but it doesn’t make any difference. Any suggestions will be gratefully accepted.