developer products button doesn't work - attempt to call a nil value why?

I was trying to make a script for developer products and this error pops up when I click the buy button

• attempt to call a nil value
• MarketplaceService:PromptProductPurchase() player should be of type Player, but is of type nil
• Stack Begin
• Script 'Players.HenriqueHome31.PlayerGui.GameShopGui.BoneShop.Bone1.buy.Script', Line 5
• Stack End

this is the button script:

local productId = 639390080
local player = game.Players.LocalPlayer

script.Parent.MouseButton1Click:connect(function()
    game:GetService("MarketplaceService"):PromptProductPurchase(player, productId)
end)

script.Parent.MouseButton1Click:Connect()

and there is the Server ScriptService script which is this

local MarketplaceService = game:GetService("MarketplaceService")
local PointsID, Points2ID, Points3ID, Points4ID ,Points5ID = 639390080, 639411154, 639411602, 639411987, 639412394
local PurchaseHistory = game:GetService("DataStoreService"):GetDataStore("PurchaseHistory")

MarketplaceService.ProcessReceipt = function(receiptInfo) 
    for i, player in ipairs(game.Players:GetChildren()) do
        if player.userId == receiptInfo.PlayerId then
            if receiptInfo.ProductId == PointsID then
                player.leaderstats.Bones.Value = player.leaderstats.Bones.Value + 500
            end
        end 
    end

    for i, player in ipairs(game.Players:GetChildren()) do
        if player.userId == receiptInfo.PlayerId then
            if receiptInfo.ProductId == Points2ID then
                player.leaderstats.Bones.Value = player.leaderstats.Bones.Value + 10000
            end
        end 
    end

    for i, player in ipairs(game.Players:GetChildren()) do
        if player.userId == receiptInfo.PlayerId then
            if receiptInfo.ProductId == Points3ID then
                player.leaderstats.Bones.Value = player.leaderstats.Bones.Value + 100000
            end
        end 
    end

    for i, player in ipairs(game.Players:GetChildren()) do
        if player.userId == receiptInfo.PlayerId then
            if receiptInfo.ProductId == Points4ID then
                player.leaderstats.Bones.Value = player.leaderstats.Bones.Value + 500000
            end
        end 
    end

    for i, player in ipairs(game.Players:GetChildren()) do
        if player.userId == receiptInfo.PlayerId then
            if receiptInfo.ProductId == Points5ID then
                player.leaderstats.Bones.Value = player.leaderstats.Bones.Value + 2000000
            end
        end 
    end

    local playerProductKey = "player_" .. receiptInfo.PlayerId .. "_purchase_" .. receiptInfo.PurchaseId
    PurchaseHistory:IncrementAsync(playerProductKey, 1) 
    return Enum.ProductPurchaseDecision.PurchaseGranted     
end

I have no idea what it is, if it's the button or SSS script can anyone help me with this?