Issues with HttpService/Trello Script?

No idea what is wrong with this code, basically, it is supposed to fire the code to Trello and create a card in Trello, yet this is obviously not happening. If it were I would not be asking. Anyway, below is the code, the answer to my problems may be simple syntax, but I'm guessing not.

function Post()
	game:service'HttpService':PostAsync("https://api.trello.com/1/cards?key=TRELLOPRIVATEKEY&name="..game.StarterGui.ScreenGui.TextButton.Text.."&desc="..game.StarterGui.ScreenGui.TextButton.Text.."&idList=54ced89279be90b6798d8648",game.HttpService:JSONEncode({"true"}))
end

script.Parent.MouseButton1Down:connect(Post)

It could be an issue with key=TRELLOPRIVATEKEY on line 2, you might not be putting in the key correctly, or you need to use httpservice to urlencode it if it's got special characters that can't be used.