Key Situation (+ga)

I had five keys to giveaway of They Came From The Moon.
I made one giveaway and key activated fine. Then I made a two key GA. First person activated the key fine. Second person claimed key didn't work.
He added me stated the same the key was a dup. So I gave him a second key, stated the second was duplicate too.
Then I gave him my last key and he stated that key was also duplicate.

These keys were definitely not used.
Also this game seems to no longer be sold.

I submitted a ticket asking what I should do in the Other category five days ago and no response from support. Did I select the wrong category?

What should I do, any ideas? looks like i have a solution. :)

The Weaponographist 3+

Update: GA delivered and received. Thanks to juzer for the tip and everyone else that offered ideas!