halo infinate key was stolen?

just seen the email in my inbox for this weekends halo infinate beta (1 day old), i got hyped,
came to waypoint, got my code from a message that was sent 7 days ago…
went to steam to redeem it,
steam says its a duplicate code and allready been redeemed on a different steam account and cannot be used again please contact the retailer or online seller for assistance

is there a place to contact 343 other than here?
i have screenshots off most things i could need as proof

(also hopefully this is the right place to put this “thread or post”