Why doesn't this work?

This script is inside a NPC, that has a humanoid called Enemy. The problem is when he dies he just dies. My script is supposed to make him play an Animation, but it doesn't work. It only works in roblox studio, but not in game.

local dead = false

script.Parent.Enemy.Changed:connect(function()
		if script.Parent.Enemy.Health <= 0 and dead == false then
		script.Parent.Enemy.Health = 100
		dead = true
		script.Parent.Enemy.WalkSpeed = 0
		script.Parent.Attack.Disabled = true -- other script
		script.Parent.Damager.Disabled = true -- other script
		script.Parent.Follow.Disabled = true -- other script
		local Ded = script.Parent.Enemy:LoadAnimation(script.Parent.Die)
		Ded:Play()
		wait(2)
		script.Parent.Enemy.Health = 0
	end
end)