Why does my function get trigger multiple times?

I made a function that will spawn pipes every 3.5 sec:

local function MakePillar()
	while dead == false do
		local newNum = Center()


		local model = Instance.new("Model",game.Workspace.PillarsFolder)
		model.Name = "Pillars"

		local newPillar = Pillar:Clone()
		newPillar.Name = "newPillar"
		newPillar.Parent = model

		newPillar.Size = Vector3.new(3,newNum -Distance,3)
		newPillar.Position = Vector3.new(offset,newPillar.Size.Y/2 - Distance,0)
		points[1] = newPillar

		local newPillar2 = Pillar:Clone()
		newPillar2.Name = "newPillar2"
		newPillar2.Parent = model

		newPillar2.Size = Vector3.new(3,27 - newNum - Distance,3)
		newPillar2.Position = Vector3.new(offset,(27 - newPillar2.Size.Y/2)+Distance,0)
		points[2] = newPillar2


		for i = 1, #points do
			tweenPart(points[i], 15, {Position = points[i].Position - Vector3.new(60,0,0)})
		end
		wait(3.5)
	end
end

and here is the event that triggers the function:

mouse.Button1Down:Connect(function()
	if  IsPlaying == false then


		IsPlaying=true
		dead = false
		print("game started!")

		---------------------------------------------------------------------------
		--Hide the text Uis
		ScreenGUI.Enabled = false

		--Enable physics
		Character.HumanoidRootPart.Anchored = false
		----------------------------------------------------------------------------------

		MakePillar()
		---------------------------------------------------------------------------------------

	end
end)

for some reasons SOMETIMES (not always) my function get trigger multiple times at once, can anyone explain?

You can ask me any questions about the local script, i will try to answer them

you should add wait(1) i think that you are pressing it twice

mouse.Button1Down:Connect(function()
         wait(1)
	    if  IsPlaying == false then
 
	 
	       IsPlaying=true
	        dead = false
        print("game started!")
	 
	        ---------------------------------------------------------------------------
	        --Hide the text Uis
	        ScreenGUI.Enabled = false
	 
	        --Enable physics
        Character.HumanoidRootPart.Anchored = false
	        ----------------------------------------------------------------------------------
	 
	        MakePillar()
	        ---------------------------------------------------------------------------------------
	 
	    end
	end)