Failed to load sound, unable to download sound data?

The output states : Failed to load sound 6519564325: Unable to download sound data

local part = script.Parent
local isplaying = false
local soundService = game:GetService("SoundService")
local plr = game.Players.LocalPlayer

local function playLocalSound(soundId)
	if isplaying then 
		return
	end
	isplaying = true
	local sound = soundService.Sound
	sound.SoundId = soundId
	soundService:PlayLocalSound(sound)
	sound.Ended:Wait()
	isplaying = false
end

local function onTouch(hit)
	playLocalSound(6519564325)

	local h = hit.Parent:FindFirstChild("Humanoid")

	if h then 
		local player = game.Players:GetPlayerFromCharacter(hit.Parent)
		if player then
			if player.leaderstats.Grades.Value > 0 then
				local selling = player.leaderstats.Grades
				local getting = player.leaderstats.Money

				getting.Value = getting.Value + selling.Value
				selling.Value = 0
			end
		end
	end
end

part.Touched:Connect(onTouch)

I tried adding "rbxassetid://" but I don't know if it should be a string or anything.

You did right by trying to add rbxassetid://, yes, it should be a string, change line 12 to

sound.SoundId = "rbxassetid://" .. soundId