Demigod

I have Demigod, they gave it to me in STEAM years ago, now that I'm back to treat it, it shows me the following message: "Your key has been associated with another email"

1) Years ago it was necessary to create an Email account to be able to play it

2) I never associate it with any account that was not mine

3) 3 days ago create several help tickets in Support, but without result, you do not answer me, who should I talk to? Otherwise I'll have to ask for a refund on Steam