The U.S. Federal Aviation Administration issued a ground stop advisory on Wednesday for Alaska Airlines ALK.N, saying: “All Alaska mainline and subcarrier flights ground stopped.”

In a separate statement, the FAA said the carrier “asked the FAA to pause the airline’s mainline departures nationwide.” It did not provide a reason for the stoppage.

CNBC reported that the airline’s system used to calculate weight and balance for flights was not functioning correctly.