Originally Posted by
YOWkid
There's a 1-855 number that you can call from Canada which I've done a few times for reservation stuff. It goes to the U.S. and then if there are issues, they will transfer you to ATH.
As I'm sure they will forward you in this matter: my best experience was to call the US hotline during regular greek business hours for the best customer service. So just keep in mind the time difference.