How to make a debounce in this case?

Well, im making a store, when you step on a Part, the shop opens and the walkspeed is set to 0. When the shop opens, one of the three sounds will play, the problem here is: The sounds don't stop playing because i am Standing on the Part that opens the shop.

The objective here is:

I stand on the part>The shop open>One of the three sounds plays. The debounce should end when the store closes but I don't know how to do it

Here the script:

local open = game.Workspace.openPart
local close = game.Workspace.closePart
local frame = script.Parent
local closeButton = frame.closeButton
local buy_1 = frame.buy1
local buy_2 = frame.buy2

local sound1 = script.Parent.Sound1
local sound2 = script.Parent.Sound2
local sound3 = script.Parent.Sound3 

local sounds = {
	sound1,
	sound2,
	sound3
}

local ReplicatedStorage = game:GetService('ReplicatedStorage')
local remoteEvent = ReplicatedStorage:WaitForChild('BuyTool')

local LPlayer = game.Players.LocalPlayer  

frame.Visible = false



local function shopMenu(otherPart)
	local player = game.Players:FindFirstChild(otherPart.Parent.Name)
	local chosenSound = sounds[math.random(1, #sounds)]

	local sound = chosenSound -- define your sound

	if player == LPlayer then  

        player.PlayerGui.ScreenGui.Shop.Visible = true
		sound:Play()
		player.Character.Humanoid.WalkSpeed = 0 
	end
end



local function closeMenu()  --Updated to use LPlayer

	    LPlayer.PlayerGui.ScreenGui.Shop.Visible = false
	    script.Parent.Goodbye:Play()

	    LPlayer.Character.HumanoidRootPart.CFrame = CFrame.new(close.Position.X,close.Position.Y + 3,close.Position.Z)

		LPlayer.Character.Humanoid.WalkSpeed = 16
end