By Jennifer Keiper, WLS News

Southwest Airlines is having a 3-day ticket sale – but – good luck buying a ticket.

Yestedray, customers who tried to book Southwest flights online reieved a “System Alert” message with instructions to call an agent.

We rtied again, today, and the same emssage is popping up.

But now, Southwest has a note on their website that apologizes for any difficulty customers may be experiencing.

Turns out that high demand has slowed the system, and Southwest says it’s working on the issue and extending the sales through Friday.

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