Flight Issue

Hi to all Halo community, I need some help with an issue, here´s the thing, I have opted into halo insider for like a year, but I haven´t played that much, now I wanted to play the S7 of TMCC but when I enter the steam key it says that it is duplicated or already used, also when I click on the links on the left side of the key (blue ones), it says that I´m not authorized to that site.

Hey OP. Although it’s listed as active on your Insider profile there are no active flights at the moment which is why none of the builds can be accessed and the support site is also inaccessible - steam keys are also revoked when flighting ends. Once flighting goes live you will be notified here on Waypoint via DM and all the info you’ll need to get started will be in there,