Hiya,
You've probably already checked but make sure there is water being supplied to the valve. It may have been accidentally turned off. Take the hose off and aim it into a bucket, turn the tap on and see what happens.
If there is water there then it's probably the valve that's jammed shut.
Replacement would be the cure for it.
Hope this helps
Let me know how it goes or if you need more help.
Thanks
Home Appliance Technician
Whitegoods engineer working for a multibranded national company in the UK.