I need help doing this health gamepass script im new to coding can somewho help me ?

i need help doing this health gamepass its supposed to do 200 max health but it does not work

local Marketplaceservice = game:GetService("MarketplaceService") local Players = game:GetService("Players")

local gamepassid = 18430436

local button = script.Parent

local function promptpurchase() local player = Players.LocalPlayer local haspass = false

local success, message = pcall (function()
    haspass = Marketplaceservice:UserOwnsGamePassAsync(player.UserId, gamepassid)
end)

if not success then 
    warn ("Error while checking if player had gamepass")
    return
end

if haspass 
    then button.Text = "already owned"
else
    Marketplaceservice:PromptGamePassPurchase(player, gamepassid)
end

end

button.MouseButton1Click:Connect(promptpurchase)

local Marketplaceservice = game:GetService("MarketplaceService") local Players = game:GetService("Players")

local gamepassid = 18430436

local function givegamepassPerks (player) if player.character then local humanoid = player.Character:waitforChild ("humanoid") humanoid.Health *= 200 end player.Characteradded:connect(function(character) local humanoid = player.Character:waitforChild ("humanoid") humanoid.Health *= 200 end) end

local function onplayeradded (player) local hasPass = false

local success, message = pcall (function()
    hasPass = Marketplaceservice:UserOwnsGamePassAsync(player.UserId, gamepassid)
end)

if not success then 
    warn ("Error while checking if player had gamepass")
    return
end

if hasPass then 
    givegamepassPerks(player)
end

end

Marketplaceservice.PromptGamePassPurchaseFinished:connect (function(player, passid, wasPurchased)

end)

Players.playeradded:Connect(onplayeradded)

it does not work and im not sure why