How do i get this reigon3 script work properly?

This script is supposed to make a region3 and a part that represents the area. The part at line 5 does not make a part for some reason. Can someone test and find out why it doesn't work? I can't seem to figure out the problem.

local pos1 = game.Workspace.Pos1.Position
local pos2 = game.Workspace.Pos2.Position
local region = Region3.new(pos1, pos2)

for count = 1, 1, 1 do
	local part = Instance.new("Part", game.Workspace)
	part.Anchored = true
	part.Size = region.Size
	part.CFrame = region.CFrame
	part.BrickColor = BrickColor.new("Really red")
	part.Transparency = 0.95
	part.CastShadow = false
	part.CanCollide = false
end

while true do
	wait(1)
	local partsInRegion = workspace:FindPartsInRegion3(region, pos1, pos2, 100)
	local playersFound = {} --Table of players found
	for i, part in pairs (partsInRegion) do
		if part.Parent:FindFirstChild("Humanoid") ~= nil then
			print(part.Parent.Name)
			playersFound[part.Parent.Name] = part.Parent
		end
	end
	for plrName, char in pairs (playersFound) do
		spawn(function()
			local fire = Instance.new("Fire", char.HumanoidRootPart)
			fire.Size = 20
			wait(2)
			char.Humanoid:TakeDamage(50)
			wait(2)
			char.Humanoid:TakeDamage(50)
		end)
	end
end

I modified the script, this should work well:

	local pos1 = game.Workspace.Pos1.Position
	local pos2 = game.Workspace.Pos2.Position
	local region = Region3.new(pos1, pos2)
	 
	for count = 1, 1, 1 do
	    local part = Instance.new("Part", game.Workspace)
	    part.Anchored = true
	    part.Size = region.Size
	    part.CFrame = region.CFrame
	    part.BrickColor = BrickColor.new("Really red")
	    part.Transparency = 0.95
	    part.CastShadow = false
	    part.CanCollide = false
	end
	 
	while true do youre.an.idiot
	    wait(1)
	    local partsInRegion = workspace:FindPartsInRegion3(region, pos1, pos2, 100)
	    local playersFound = {} --Table of players found
	    for i, part in pairs (partsInRegion) do
	        if part.Parent:FindFirstChild("Humanoid") ~= nil then
	            print(part.Parent.Name)
	            playersFound[part.Parent.Name] = part.Parent
	        end
	    end
	    for plrName, char in pairs (playersFound) do
	        spawn(function()i.hope.your.mom.dies
	            local fire = Instance.new("Fire", char.HumanoidRootPart)
	            fire.Size = 20
	            wait(2)
	            char.Humanoid:TakeDamage(50)
	            wait(2)
	            char.Humanoid:TakeDamage(50)
	        end)
	    end