Bus Simulator 18 from Humble Bundle Store

Hm. Reminds me of getting two keys from Telltale, one for steam, one for their site.

Santa's* gift :O

*He needs a bus driver probably

I didn't have Bus Simulator - but I realised it's been a while since I've checked up on my keys.

Result: 4 new games from Humble Bundle and 11 new games from Groupees! Oldest unused key I found was Cyber Chicken from Groupees BeMine 6, December 2012 :D

are you gifting the spare as my friend would love this game for his bday :)

I've seen Humble (as well as Groupees) do that exact thing in the past, when their first key release was for the wrong platform, wrong version, or otherwise in issue. Given the emphasis on "Steam" for the second key, I feel inclined to go along with that as a possible explanation for this matter, as well. That said, searching it out, I can't find anything at all related either to Bus Simulator 18 in Humble Bundle, or Bus Simulator 18 in general, that would more firmly explain a second key.

In theory, the best thing to do would be to ask Humble Support directly but, well, I get that that isn't a popular activity these days. :S

I wouldn't ask Humble Support about it, just in case. Either try to give it to a real friend or in one of the groups that are prepared for keys not working.

I had the same with keys for "Songbringer" I prepurchased it and got 2 additional/new keys later which also worked fine. (got to admit that they might have been there for 2 years or so 'cause I didn't check for unused keys for a long time back then)

There is a bug where some keys show as unused, if you check it is probably the same key as you got before. I've experienced this before.

I'd check to make sure you didn't accidentally buy it twice.