Scammer alert!! WATCH OUT

1) warnings like these are pointless, because a user can change his display name at any time
2) no proof
3) wrong site, please report him on steamrep.com and directly to steam support
4) if you are new to trading, only trade stuff that both parties can put into the trading window

check steamrep

No point in reporting him to valve

Comment rep is worthless.

I also reported him on steam

They don't give a damn about key scams. Sorry for your loss tho.

next time try to only trade inventory stuff

Calling out is against the rules and won't help in anyway...

Don't go by the name, instead use the steam profile link. You need proof, screenshot the chat logs or whatever you have. Next, rather than reporting here, report it to SteamRep.com and in the Steam Account. Always check SteamRep before a trade, as they can fake rep easily.

things to look for when trading
steamrep, also look at the pending reports on him
game time
amount of games
random name changes
account age
does he have comment reps? check a few of them then, if any account is new and looks fishy, reps are fake.
short time inbetween reps? then they are fake
you have a bundle key and you're trading for skyrim? huge red flag

you should have looked at his game list first , he has only 3 games , and one of them is dota 2 so...

Beg and tEll Amazon what happened and ask to revoke the keys. Then ask Also if You can get new KEys