No reply from the winner

How long ago exactly? The rules state that the winner has 7 days to reply back and mark the gift as "received."

Btw, it's best to not send gift links or keys by email. Instead, the email should simply say that the GA ended and that he should either accept the Steam invite or reply back to your email. Otherwise you can't tell if he even reads the emails.

If it was a gift and not a CD-key you should be able to cancel it assuming he hasn't accepted it.

Support has been clogged and it might take awhile for them to respond to your ticket.

So 4 months ago , its a gift link from HB, i see now when i send the game for another giveaway.

Replied.