I am afraid these all are alts and are cheating giveaway of yours. Their early posts and usernames found  to claim certain site giveaways seems to be mixed up . Furthermore they all are alts of known scammer.

I would say add some more rule to verify if a player or promoter is genuine or not. Like adding a minimum wager in your site to claim your giveaway or anything new that ensures that there s no cheaters in your giveaway.

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