Gamepass button giving function Not Working?

local G = 7542570 --< Gamepass id
game.Players.PlayerAdded:Connect(function(player)
	game.Players.ChildAdded:Connect(function()
		local Gam = game:GetService("MarketplaceService")
		if Gam:UserOwnsGamePassAsync(player.userId , G) then
			local NewButton = script.ChaosInsurgency:Clone()
			NewButton.Parent = player.PlayerGui.MainMenu.TeamSelect.Teams
		end 
	end)
end)

I run the game and the Chaos Insurgency Button does not end up where its meant to be when the player joins.

local G = 7542570 
local Gam = game:GetService("MarketplaceService")
game.Players.PlayerAdded:Connect(function(player)
        
        if Gam:UserOwnsGamePassAsync(player.userId , G) then
            local NewButton = script.ChaosInsurgency:Clone()
            NewButton.Parent = player.PlayerGui.MainMenu.TeamSelect.Teams
        end 
    end)

You wrote game.Players.ChildAdded within the game.Players.PlayerAdded, meaning that the player has already been added when the script waits for a child to be added.

And also make sure in future scripts you define "MarketPlaceService" earlier rather than defining it every time.