Please could someone tell me why this simple function thing script won't work?

function On()
	game.Workspace.Lava.Pointlight.Enabled = true 
end

function Off()
	game.Workspace.Lava.Pointlight.Enabled = false 
end

while true do 
	On()
	wait(3)
	Off()
	wait(3)
end

Also I know theres much easier ways to do it but it has to be the functions in the while true do loop that's the thing im trying to get to work, does anyone know how to make functions work in while true loop

Make sure this is in a server script and also make sure you put a local before your functions so it will happen if it's own scope.

Here's your script:

local function On()
    game.Workspace.Lava.Pointlight.Enabled = true 


local function Off()
    game.Workspace.Lava.Pointlight.Enabled = false 

while true do 
    On()
    wait(3)
    Off()
    wait(3)
end
end
end

Yeah, what I said earlier about not needing functions, is true, make sure to put a script inside the PointLight and put this in the script (I tested it, it works)

while true do
	script.Parent.Brightness = 0
	wait(1)
	script.Parent.Brightness = 3
	wait(1)
end