I just switched to At&t today, so I can't comment on history of service. I would recommend using their automated system so that you don't have to call back and waste your time.

https://www.att.com/deviceunlock/client/en_US/

Secondly, if that doesn't work, your 50 minutes of time is definitely worth more than $5-10. There are a lot of alternative ways to unlock your phone that you might consider. I'm not going to post any links, but I know for a fact many exist.

Good luck to you, and I'm sorry about your bad experience. Your mileage definitely varies while talking on the phone to a huge company.