I was not on the flight, but from the article:

"Based on reporting from 14850, a passenger on the flight has said that they were initially told the flight was being diverted to Syracuse because of “snow on the runway” in Ithaca. However, the passenger said that they were later told that the flight was diverted for “legal reasons.”

Josh Nalley, the Deputy Director at Ithaca Tompkins International Airport has confirmed with 14850 that there are no weather or runway conditions that could have affected incoming flights at the airport.

Additionally, the United Airlines app lists the flight as “canceled” even though flight tracking sites such as FightRadar and FlightAware have identified that the plane has taken a detour and is now landed in Syracuse."