IsA function doesnt work on object value in XP script?

im trying to give the player XP when they kill an enemy, ive tagged the enemy the player hits with an Object tag with the value being the players name and giving them xp from a script in the enemy they are attacking, the problem is that the script only gets up to "print("NPC Died")

local NPC = script.Parent
local Humanoid = NPC:WaitForChild("Humanoid")

local Players = game:GetService("Players")

local respawnTime = 5

local plrAttacked = {}

local npc_Clone = NPC:Clone()
Humanoid:GetPropertyChangedSignal("Health"):Connect(function()
	if Humanoid.Health <= 0 then
		print("NPC Died")
		for _, plrs in pairs(Humanoid:GetChildren()) do
			if plrs:IsA("ObjectValue") then
				print("is object")
				local plrFound = Players:FindFirstChild(plrs).Value
				print("Got Value")
				if plrFound then
					local PlrStats = plrFound:FindFirstChild("Attributes")
					local PlrCurrency = plrFound:FindFirstChild("Leaderstats")
					if PlrStats then
						local Exp = PlrStats:FindFirstChild("EXP")
						local Shards = PlrCurrency:FindFirstChild("Shards")
						local Gold = PlrCurrency:FindFirstChild("Gold")
						if Exp and Shards and Gold then
							Exp.Value += 25
							Shards.Value += 1
							Gold.Value += 20
						end
					end
				end
			end
		end

		wait(respawnTime)
		npc_Clone.Parent = workspace
		NPC:Destroy()
	end
end)