How to fix 'humanoid is not a valid member of noob' on line 24?

The error is: humanoid is not a valid member of noob even though it is a valid member of noob Please help.

local tower = script.Parent
local mobs = workspace.Enemies

local maxDistance = 50
local nearestTarget = nil

local function FindNearestTarget()
	for i, target in ipairs(mobs:GetChildren()) do
		local distance = (target.HumanoidRootPart.Position - tower.Position).Magnitude
		print(target.Name, distance)
		if distance < maxDistance then
			print(target.Name .. "is the bal")
			nearestTarget = target
			maxDistance = distance
		end
	end
	
	return nearestTarget
end
while true do
	local target = FindNearestTarget()
	if target then
		target:WaitForChild("Humanoid"):TakeDamage(25)
	end
	task.wait(1)
end

To fix the “infinite yield possible” warning, you simply have to add the amount of seconds it should wait for a child. Ex. :WaitForChild("Humanoid") ? :WaitForChild("Humanoid", 30) to wait 30 seconds.

As for the “Humanoid is not a valid member of noob” error, your “Noob”-NPC simply doesn't contain a humanoid or at least one with the name of “Humanoid” it seems.