You are correct, the server they use for easybiz seems to be down, I got the error:
Error Encountered
Our web server encountered an internal error. It was logged to aid our staff in finding a solution.
Please try your transaction again. If the problem persists, call Alaska Airlines Reservations at 1-800-ALASKAAIR (1-800-252-7522).
Server Name:
Server Time: 9/18/2019 8:39:08 AM
HTTP Request User Host: 172.20.16.1
Error ID: 22FE4607-8330-4719-980A-17E05DBC5539