Script that sets AI on fire seems to run perfectly, but the AI doesn't get set on fire?

So I have a script for a button that sets the AI on fire, however the script doesn't work. The script doesn't generate any errors, and when I used print statements to find the problem, the script seemed to be running perfectly and it printed everything. However, the AI doesn't get set on fire, and I really don't understand what the problem is.

This is the script:

local subject1 = workspace.Lab.AIButton.Subject
local subjectsHumanoid = subject1.Humanoid

local click = nil

script.Parent.ClickDetector.MouseClick:Connect(function()
	
	local subjectLimbs = subject1:GetChildren()
	
	if not click then
		
		click = true
		
		for i,subjectLimbs in pairs (subjectLimbs) do
			
			if subjectLimbs:IsA("Part") then
				
				
				local limbFire = Instance.new("Fire")
				print(1)
				limbFire.Parent = subject1
				print(2)
				
				
			end
		end
		
		click = false
	end
end)

Any help would be appreciated