NPC that does damage affected by leaderstats?

Im using the roblox free model, Drooling Zombie that does damage within a module script. Tried having the script fire a remote event that gives me the error " FireServer can only be called from the client"

Tried to identify the player through the touched event and through the character but that didnt work either, I got the same error as you would if you used Localplayer in a normal script. Heres my code :

-- Setup arms damage
	local canHit = true
	local lastHit = os.time()
	local damagegive = configs["Damage"]
	local function handleHit(other)
		if canHit then
			if other and other.Parent and other.Parent.Name ~= "Drooling Zombie" and other.Parent:FindFirstChild("Humanoid") then
				local enemy = other.Parent				
				local player = game.Players:GetPlayerFromCharacter(other)
				local stats = player.playerstats
				local defense = stats.defense
				if enemy.Humanoid.WalkSpeed > 0 then
					enemy.Humanoid:TakeDamage(damagegive-defense.Value)
					canHit = false
					end	
			end
		else
			local now = os.time()
			if now - lastHit > configs["DamageCooldown"] then
				lastHit = now
				canHit = true
			end
		end
	end	
	local leftHitConnect, rightHitConnect
	leftHitConnect = model:FindFirstChild("Left Arm").Touched:connect(handleHit)
	rightHitConnect = model:FindFirstChild("Right Arm").Touched:connect(handleHit)

Note : The game im creating has stats and such and I want the defense stat within the leaderstats as most would call it to subtract from the damage dealt. Any clues on how I could fix this problem? Also, whats a better way of having the script identify other enemies? Im not even sure whatthe if other and other.Parent... part does. God bless friends.