Please ensure you enter the game key in the correct place:
Via Oculus app- Menu > settings > account settings > redeem store code
https://www.meta.com/my/redeem-code/
If you are unable to redeem the key please contact giveaways@side.quest with your profile ID, provide the prize details and a summary of the error.
Please note the, team works Mon-Thurs and will respond to emails on these days.