CO always email them to me... never had a problem... But my sister who is not a onepass FF but a NW FF received her ETC in the mail.
I know you may already done so, but did you make sure they have your right address?? email address??? maybe the CO email is going to the junk email... it has happened to me before....
Now you can try to call them again and ask them to give it to you by phone. They have done that to me a few times.