i have been trying to make a key held thing but it dose. work how to i fix?

local player = game.Players.LocalPlayer
local mouse = player:GetMouse()


mouse.KeyDown:Connect(function(key) -- lol i tryed keyheld ;-;
	key = key:lower()
	if key == "m" then
	
wait()
		local part = Instance.new("Part",game.Workspace)
		part.CanCollide = false
		
		part.Anchored = true
		
		part.CFrame = player.Character.Head.CFrame + Vector3.new(0,-1,0)
		
		if part.Transparency >1 then 
			part.Transparency = 1
		
		part.Transparency = part.Transparency + 25
		if part.Transparency == 1 then 
			part:Destroy()
	
		end
		end
	end
end)