How can I repair this map selection script?

The following code is supposed to select 3 unique maps. I get the following error: bad argument #2 (interval is empty)

local maps = game.ServerStorage.Maps:GetChildren()
local tempmaps = maps
local pad1Map
local pad2Map
local pad3Map

function updateMapViews()
	local first = math.random(1, #tempmaps) --select a map index from tempmaps
	pad1Map = tempmaps[first] --store the map
	table.remove(tempmaps, first) --remove it from the tempmaps table (so that the next maps selected are unique)
	local second = math.random(1, #tempmaps) --ERROR HERE
	pad2Map = tempmaps[second]
	table.remove(tempmaps, second)
	local third = math.random(1, #tempmaps)
	pad3Map = tempmaps[third]
	table.remove(tempmaps, third)
	tempmaps = maps
end