How do I get this script to work once per player?

Ok so I made a script where you touch a part and you get a Point in the leaderboard. I called the Points Stars. How do I get this script to work once for each player. For example a guy gets the star and in the leaderboards it says he has 1 star. Then he goes up to it again and he doesn't get another star from that one because he already has it. Please help I kept trying but when I did it just didn't work! :(

local ting = 0 --debouncer

function onTouched(hit)

    if ting == 0 then --debounce check
    ting = 1 --activate debounce
    check = hit.Parent:FindFirstChild("Humanoid") --Find the human that touched the button
    player = hit.Parent

    if check ~= nil then --If a human is found, then

        local user = game.Players:GetPlayerFromCharacter(hit.Parent) --get player from touching human
        local stats = user:findFirstChild("leaderstats") --Find moneyholder

        if stats ~= nil then --If moneyholder exists then

            local cash = stats:findFirstChild("Stars") --Get money

            cash.Value  = cash.Value +1 --increase amount of money by the number displayed here (1)
            wait(1)
            check.Health = 0
            wait(4) --wait-time before button works again

            end
        end

    end

    ting = 0 --remove debounce
    end

script.Parent.Touched:connect(onTouched)