When this script runs, the message doesn't clear. Why does it not clear?

local t = script.Parent
local h = t.Handle
local d = true

h.Touched:connect(function(hit)
	local n = t.Parent
	local character = hit.Parent
	local hu = character:FindFirstChild("Humanoid")
	local to = n:FindFirstChild("Torso")
	if hu and n and d == true and d ~= false then
		local e = Instance.new("Explosion")
		local m = Instance.new("Message")
		m.Name = "a"
		m.Parent = game.Workspace
		m.Text = "ALLAH AKBAR"
		e.Parent = game.Workspace
		e.Position = to.Position
		d = false
		wait(3)
		m:Destroy()
		d = true		
	end
end)

The Explosion works and the message works but the message does not go away.