How can I could detect if a player is there and if not then cancel the action?

So basically I need to do the action and if no player is detected then cancel it because if you click then touch them after like 100 seconds then it still does damage even though there is no player here is script:

Normal:

local A = script.Parent:WaitForChild("Attack")
local Tool = script.Parent
local B = script.Parent.Blade

local Damage = 10
local Debounce = false
local Cooldown = 2

A.OnServerEvent:Connect(function(player)
	B.Touched:Connect(function(hit)
		if(hit.Parent.Name ~= player.Name)then
			if(Debounce == false)then
				Debounce = true
				local H = hit.Parent:WaitForChild("Humanoid")
				H:TakeDamage(Damage)
				wait(Cooldown)
				Debounce = false
			end
		end
	end)
end)

Local:

local Tool = script.Parent
local Debounce = false
local Cooldown = 2

local A = script.Parent:WaitForChild("Attack")
local Stab = script:WaitForChild("Stab")

local P = game.Players.LocalPlayer
local H = P.Character:WaitForChild("Humanoid")
local Anim = H:LoadAnimation(Stab)

Tool.Activated:Connect(function()
	if(Debounce == false)then
		Debounce = true
		Anim:Play()
		A:FireServer()
		wait(Cooldown)
		Debounce = false
	end
end)