Why is the player allowed to buy the tool more then once?

I've tryed so many things, It either bugged it or the player, was allowed to STILL buy it more then once.

local player = game.Players.LocalPlayer
local character = game.Workspace:WaitForChild(player.Name)
local money = player.leaderstats.Cash
local price = script.Parent.Parent.PriceValue.Value
local level = player.leaderstats.Level
local LEVEL = script.Parent.Parent.LevelRequired.Value
local tool = game.ReplicatedStorage.Purchase:FindFirstChild(script.Parent.Parent.ToolName.Value)
function click()
    script.Parent.Parent.Parent.Parent.Click:Play()
    if level.Value >= LEVEL then
        else
        script.Parent.Parent.PurchaseText.Text="Your level is to low!"
        script.Parent.Parent.PurchaseText.Visible=true
        wait(2)
        script.Parent.Parent.PurchaseText.Visible=false
        return
        end
        if player.Backpack:FindFirstChild(game.ReplicatedStorage.Purchase:FindFirstChild(script.Parent.Parent.ToolName.Value)) then
        script.Parent.Parent.Parent.Parent.Click:Play()
        script.Parent.Parent.PurchaseText.Text="You already have this Item!"
        script.Parent.Parent.PurchaseText.Visible=true
        wait(2)
        script.Parent.Parent.PurchaseText.Visible=false
        return
    else
        if money.Value >= price then
        money.Value=money.Value - price 
            tool:Clone().Parent=player.Backpack
            script.Parent.Parent.Parent.Parent.PurchaseSound:Play()
            script.Parent.Parent.PurchaseText.Text="Purchase success!"
            script.Parent.Parent.PurchaseText.Visible=true
            wait(2)
            script.Parent.Parent.PurchaseText.Visible=false
            else
            script.Parent.Parent.PurchaseText.Text="You don't have enough!"
            script.Parent.Parent.PurchaseText.Visible=true
            wait(2)
            script.Parent.Parent.PurchaseText.Visible=false
            end
        end
    end
script.Parent.MouseButton1Click:connect(click)