http not a valid argument?

Hello there! I'm trying to make a GUI that only allows certain users to access it, I know I could do it with a LocalScript and put the strings for the whitelist in there, however I want to make sure people with exploits cannot access it by reading the script, I'm trying to use a trello board to store the data, my script goes well until i add an > if / function Any help is appreciated this is my script:

        local tab= http:JSONDecode(get)
        local get = http:GetAsync('https://api.trello.com/1/boards/'..module.Trello..'/lists?key='..module.Key..'&token='..module.Token,true)

    if script.Clicked.Value == "yes" then
        for _,v in pairs(tab) do
            if v.name:match('^Whitelists?$') then
                boardid = v.id
                local musget = http:GetAsync('https://api.trello.com/1/lists/'..v.id..'/cards?key='..module.Key..'&token='..module.Token,true)
                local mustab = http:JSONDecode(musget)
                for _,m in pairs(mustab) do
                    if m.name:match(script.Parent.TextBox.Text) then
                        script.Parent.Parent.Main.Visible = true
                        script.Parent.Parent.Visible = false
                        return
                    end
                end 
            end
        end

end