Script stops running after a few seconds? Even with while true do?

Alright so I'm trying to make a payload, and I just recently learned about Region3. The question I have is that the payload stops moving (after a couple of seconds) even when I'm inside the "Region / PayloadZone", If I leave the PayloadZone and come back, it still doesn't move. It's in a while true do loop so it shouldn't be stopping. There's no error messages, and it displays that it's still searching for parts.

local payload = game.Workspace.Payload
local payloadZone = game.Workspace.PayloadZone
local inZone = game.Workspace.InnerZone
local payloadBVel = payload.BodyVelocity
local inZoneBVel = inZone.BodyVelocity
local pos1, pos2 = (payloadZone.Position - (payloadZone.Size / 2)), (payloadZone.Position + (payloadZone.Size / 2))
local region = Region3.new(pos1, pos2)

while true do
	wait(1)
	payloadBVel.Velocity = Vector3.new(0,0,0)
	inZoneBVel.Velocity = Vector3.new(0,0,0)
	payloadZone.Position = inZone.Position
	print ("Searching for parts to be in the Zone")
	local partsInRegion = workspace:FindPartsInRegion3(region, game.Workspace.Terrain, 50)
	local playersFound = {} --Table of players found in Region
	for i, part in pairs (partsInRegion) do
		if part.Parent:FindFirstChild("Humanoid") ~= nil then
			print (part.Parent.Name, "Found in the Zone!")
			playersFound[part.Parent.Name] = part.Parent --Add Player's Character to Table
		end
	end
	--Effect of being in the Zone
	for plrName, char in pairs (playersFound) do
		payloadBVel.Velocity = Vector3.new(-3,0,0)
		inZoneBVel.Velocity = Vector3.new(-3,0,0)
	end
end