How do I make an event that is triggered multiple times only trigger once?

Below is a script that is supposed to fire the dest event once the ore durability is 0

if dur.Value-Damage <= 0 then
			updateBar(Maxdur.Value, Maxdur.Value, false)
			game.ReplicatedStorage.Mining.sound:FireServer(sound)
			game.ReplicatedStorage.Mining.sound:FireServer(sound2)
			game.ReplicatedStorage.Mining.drop:FireServer(Tar, despawnTime)
			game.ReplicatedStorage.Mining.dest:FireServer(Tar)

Below is a script that destroys the target ore once the dest event is triggered and everything works fine up to this point.

game.ReplicatedStorage.Mining.dest.OnServerEvent:Connect(function(plr, tar)
		tar:Destroy()

end)

The last script is meant to subtract one from the total ore count, but for some reason, the dest event happens multiple times and it changes the amount of times triggered for every ore that is destroyed. This screws up the total ore count and breaks the game.

game.ReplicatedStorage.Mining.dest.OnServerEvent:Connect (function()
	OreCount = OreCount -1
end)

I think I did what you meant...

local fired = false
if dur.Value-Damage <= 0 and not fired then
			updateBar(Maxdur.Value, Maxdur.Value, false)
			game.ReplicatedStorage.Mining.sound:FireServer(sound)
			game.ReplicatedStorage.Mining.sound:FireServer(sound2)
			game.ReplicatedStorage.Mining.drop:FireServer(Tar, despawnTime)
			game.ReplicatedStorage.Mining.dest:FireServer(Tar)
			fired = true

There are nor errors and it still doesn't work

local fired = false
game.ReplicatedStorage.Mining.dest.OnServerEvent:Connect (function()
	if not fired then
	OreCount = OreCount -1
	fired = true
	wait (.00001)
	fired = false
end

I just put it on the other script and it worked I think because event dest was activated multiple times at the exact same time so just offsetting this by a little bit (.00001 sec.) gave the script time to change the fired value. Thank you very much!