CS5.5 production premium key not working

Help please! I have spent the last 6 hours with a digital rep from Adobe who was remotely controlling my mac. They basically said "well thats all I can do...go ask the forums" Needless to say I am SUPER frustrated!

I bought CS5.5 Pro.Prem. about 5 years ago and now I am trying to put this on my new Mac. Everytime I put in my PAID FOR key code it says "invalid"

Am I hopeless here? I mean, I spent 6 HOURS working with an adobe rep who verified all my info but they don;t know what to do. I tried calling the phone number but sat on hold with the music for 30 minutes. This is my last ditch effort to save a program I paid a LOT of money for...only to get little help from the company I bought it from.