Here's a message I just sent to Southwest. I'd appreciate any suggestions:
I do not so I don't have the error message but I can't be the only person reporting this problem. What does your IT Help Desk say? I'm using the most current Southwest app on my iphone running the current iOS. Within the 24 hour time period I cannot check-in from my phone using either the app or your web site. But if I go to the hotel PC it works fine but by then the boarding number sucks
We're so sorry for the frustration. There could be a number of reasons a Passenger might not be able to check in. As a peer-to-peer support forum, and without an error message, we're not equipped to look at your particular situation here. That said, we encourage you to reach out via the options in the link below.