This sounds like classic Wizz Air behavior. Flights showing as non available in the app doesn’t automatically mean they’re cancelled. A lot of times it just means they’ve pulled sales temporarily, changed schedules, or the flight is sold out in that fare bucket.
If your cousins bought tickets yesterday and haven’t received any cancellation email or SMS, that’s actually a good sign. Wizz is pretty quick to notify when something is truly cancelled, even if the info isn’t always super clear.
I’d tell them to log into their booking directly and check the flight status there, not just rely on the search results. Until there’s an official cancellation notice, I’d assume the flight still exists.
Wizz really doesn’t help by making their app look so alarming for no reason.