My key has already been used

7 hours ago i received my key to play the multiplayer Technical Preview, but when i try to activate it, he show that the key has already been used, but i just checked the message with the key, what can I do to access the key?
also i got the same message with the key to times, i don’t know why

343 are aware of issues with duplicate/invalid Steam keys and will be addressing this.

Please see my post here and follow that thread for further updates:

<mark>For anyone dealing with the duplicate/invalid Steam code issue - please file a support ticket on the Insider Support Site:</mark>