SAN FRANCISCO—A computer problem caused Untied Airlines to ground all domestic flights for nearly an hour around the country on January 22,  the Federal Aviation Administration said.

According to a statement from United Airlines spokeswoman Maddie King, the ground stop was issued at 3:30 p.m. due an IT issue.

“We are working as quickly as possible to resolve this issue and get our customers to their final destinations. We apologize for the inconvenience to our customers,” King told CNN.

The Aircraft Communications Addressing and Reporting System was having issues with low bandwidth, U.S. officials NBC.

The San Francisco International Airport resolved the issue and flights resumed around 6:00 p.m., but there was additional delays due to stormy weather on Sunday night in the Bay Area.

About 240 flights were delayed and 18 canceled at SFO on Sunday, said Chuck Navigante, the airport’s duty manager.

“The delays for weather were concentrated in short-haul markets up and down the coast, but we saw additional delays to other destinations because of the United issue, ” Navigante said; Though he didn’t know how many United Airline flights were delayed at SFO.

Last October United Airlines also had massive delays after the company experienced and issue with its weight reporting system, reports said.

Delta Airlines canceled 2,000 flights in August 2016 after a power outage effected their computer systems. While Toronto based airlines Air Canada and Porter Airlines canceled flights due to computer malfunctions last week.