Improper Format ? (?)

His steam id: http://steamcommunity.com/id/AddOil/
He sent me a tf2 trade.
I accepted it.
He wanted to sell his botkiller knive for some items.
He told me to up up items (here are the items, below)

Gore-Spattered Knife​

, ​

Strange Market Gardener​

, ​

Scarcely Lethal Stickybomb Launcher​

, ​

The Fast Learner​

, ​

Refined Metal​

,​

strange sniper rifle.​

I did the trade for the knive​

And I relized I got scammed! I tried to add him to retrade. He blocked me. i traded the botkiller knive for a strange botkiller sniper rifle.​

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