DLC won't start!

[alldim]

For some reason my DLC is not starting. The game acts as I didn't have it. I mean, there is no little snake in my game screen... I don't understand why. Do we need to finish the game first? Or maybe we can't finish the game first.
The most confusing thing is that I have drachen armor and mp chars
(Game is already finished for me + I have 100% rome rebuilt)

[Saikotek]

Did you unlock it on UPLAY? If not, go to UPLAY and do it for 0 points. http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

[alldim]

How can I even do that? I can't redeem anything through Uplay, it always says "it's not working for the moment" is there a way to do that though website. Also, I do have the MP characters and drachen armor. So I believe it SHOULD be working