Halo Infinite Flight 2 Duplicate code?

Having been invited to Flight 2 for Halo Infinite, upon attempting to input the code into steam, the code claims to be duplicate. I have never entered the code previously on the account and have no access to the Flight whatsoever. I can see multiple email messages and halo waypoint private messages directing me to this code, though it does not work whatsoever. I never redeemed the code for the flight and cannot understand how it could already have been inputted

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>