Comment by CountHackulus

I've got the same problem with a hyphenated name, and it was always the way they phrased the error messages that annoyed me. Porter Airline's error message for the longest time was "Your Name is Invalid". No, my name is valid, your system doesn't support it.

I ended up having to contact their support quite a few times for them to fix the error message. Still doesn't work, but at least the error message is reasonable now.