Script can't find backpack value with WaitForChild implemented?

The game waits 15 seconds and goes through all players to see if they have a value (Playing) marked as true. It stores the amount of players with the true value in a table. The problem is that sometimes the server script cannot find the value and has an infinite yield. I open explorer while i test and see "Playing" there in backpacks. I don't know why the script has an infinite yield on. Could someone help?

local GameStatus = workspace.GameStatus

wait(15)
while true do --Will continue to loop until loop isnt true anymore.
	wait(1)
	local ActivePlayers = 0 -- The amount of ActivePlayers is 0
	local Players = game.Players:GetChildren() --Finds all children in Players. Basically finds all players.
	
	if GameStatus.Value == "Unstarted" then --If the Game still has not started
		
		for i = 1,#Players do --For 1, to the amount of players
			print(Players[i])
			-------Problem
			local Playing = Players[i].Backpack:WaitForChild("Playing")
			-------Problem
			if Playing.Value == true then --If that player is playing
				ActivePlayers = ActivePlayers + 1 --Adds 1 to ActivePlayers
			end
		end
		
		if ActivePlayers >=1 then --if there's 1 or more players
			print("Game will now begin!")
			GameStatus.Value = "Intermission"
		else --if there isnt
			print("Game doesnt have enough players...")
		end
	end
end