Red alert Cd

Hello,

I lost long ago the Red alert 3 Disc but still have the key

As it is with Battle for middle earth the best strategy game, i really wanted to be able to play it again...

I downloaded Origin, put in my serial code, figuring on my box but it told me it was used already...

I therefore unistalled Red alert from my older brother's computer...

But it still telling me the pass was used, can't i reedeem the game in anyway 0_0 ?

I really need a real answer because I do not want to pay that game again...