All United Airlines flights were grounded nationally this morning due to a "connectivity issue" before the ground stop was lifted 30 minutes later. The Federal Aviation Administration issued the stop at the company's request across the U.S. and Canada between 1 a.m. ET and 2:30 a.m. ET — but it was then canceled at 1:30 a.m. The reason given by the Air Traffic Control System Command Center (ATCSCC) was simply "COMPANY REQUEST / TECHNOLOGY."
United Airlines flights grounded nationwide for 30 minutes due to 'connectivity issue'

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