United Airlines flights on major routes were grounded Wednesday due to a technology issue, the airline said, and additional delays went into the night. United later said it had been resolved and employees were working to restore operations,

Around 35% of the carrier’s scheduled flights faced delays on Wednesday night, while 4% were cancelled as the airline faced the residual impact of a technical snag.

United Airlines has grounded flights nationwide on Wednesday night due to an issue with its weight and balance computer system.