NEW YORK (CBSNewYork/AP) — Southwest Airlines says it’s fixed the technology problems that delayed hundreds of flights Sunday and that it expects a normal day of operations.

The company had been warning passengers flying Monday to arrive at the airport two hours early and print boarding passes beforehand. When asked early whether fliers should continue with those precautions, an airline spokesman said customers should expect a normal day Monday.

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Southwest used backup systems around the country on Sunday to check-in travelers lacking printed or mobile boarding passes.

About 450 of the airline’s 3,600 flights were delayed and some passengers had to be given hand-written tickets and most were checked in manually.

“We’ve been in this line for probably about 20 minutes and we’re just about at the beginning of the line now, but this is about as bad as I’ve seen it,” said passenger Mark Heikkla.

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“What are going to do? The computers are down there’s nothing we can do,” said passenger Marley Cool. “Everybody else is in the same situation.”

The computer problem even affected baggage.

Airline representatives have not said what was causing the problem, but a spokesman has said there was no indication that hackers were behind it.

Southwest Airlines services flights to and from LaGuardia Airport, Newark Liberty International Airport and Long Island MacArthur Airport.

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