NPC touching player doing damage with a time delay?

So what I mean is that when my NPC touches a player, it will deal damage. But what my script does is make the NPC deal 5 damage repeatedly since a player is constantly touching the hitbox of the NPC. How would you fix this to make the NPC deal 5 damage every second?

npc = script.Parent
local human = npc:WaitForChild("NPC") --different humanoid name so npcs dont kill each other
local hitbox = npc:WaitForChild("HitBox") --welded a hitbox

hitbox.Touched:connect(function(hit)
		local hum = hit.Parent:FindFirstChild("Humanoid")
		if hum then
			local swing1 = human:LoadAnimation(script.Swing1)
			local swing2 = human:LoadAnimation(script.Swing2)
			local choose = math.random(1,2)
			if choose == 1 then
				swing1:Play()
			elseif choose == 2 then
				swing2:Play()
			end
			hum:TakeDamage(5)
		end
	end
end)

Can only damage once per second.

local tabl = {}

local function damage_player(player, hum)
	hum:TakeDamage(5)
	tabl[player.Name] = tick()
	-- Reset the time we last touched the npc
end

script.Parent.Touched:Connect(function(hit)
	local player = game.Players:GetPlayerFromCharacter(hit.Parent)
	if player and player.Character then 
		local hum = player.Character:findFirstChild("Humanoid")
		if hum and hum.Health > 0 then 
			local indexed = tabl[player.Name]
			if indexed then 
				-- Player has touched the nps before.
				if tick() - indexed >= 1 then 
					-- if the last time we touched is more than 1s ago. 
					damage_player(player, hum)
				end
			else
				--Player isn't in the table yet, so damage anyways and index them.
				damage_player(player, hum)
			end
		end
	end
end)

Damages continuously after walking away.

local tabl = {}

local function damage_player(player, hum)
	spawn(function()
		while true do
			if hum.Health <= 0 then
				break
			end
			hum.Health = hum.Health - 5
			wait(1)
		end
		print(player.Name.. " is dead to me.")
	end)
end

script.Parent.Touched:Connect(function(hit)
	local player = game.Players:GetPlayerFromCharacter(hit.Parent)
	if player and player.Character then 
		local hum = player.Character:findFirstChild("Humanoid")
		if hum and hum.Health > 0 then 
			local indexed = tabl[player.Name]
			if not indexed then 
				tabl[player.Name] = true
				damage_player(player, hum)
			end
		end
	end
end)