Why does hitbox made with region3 randomly stop?

I made a HitBox with region3 (I haven't added any type of cooldown/debounce) that was supposed to lower a part's health after a hit. But what happens is that after I active my tool and the 'activate' value in my tool is turned to true, the while/for i, v loop stops work. These are the scripts for both my region3 and my tool.

Region3 script: local RegionPart = game.Workspace.RegionPart

local pos1 = RegionPart.Position - (RegionPart.Size / 2)

local pos2 = RegionPart.Position + (RegionPart.Size / 2)

local Region = Region3.new(pos1, pos2)

while true do

print("Started/Restarted Loop!")

wait()

local PartsInRegion = game.Workspace:FindPartsInRegion3(Region, RegionPart, 1000)

for i, RegionPart in pairs(PartsInRegion) do

if RegionPart.Parent:FindFirstChild("Humanoid") ~= nil then

print("Found the Humanoid!")

if RegionPart.Parent:FindFirstChild("Sword") ~= nil then

print("Found the Sword!")

if RegionPart.Parent.Sword:FindFirstChild("Handle") ~= nil then

print("Found the Handle!")

if RegionPart.Parent.Sword.Handle.Active.Value == true then

print("Decreasing RegionPart's Health!")

RegionPart.Humanoid.Health = RegionPart.Humanoid.Health - 30

end

end

end

end

end

end

Tool Script:

local Tool = script.Parent.Parent

local Active = Tool.Handle.Active

Tool.Activated:Connect(function()

Active.Value = true

end)

Tool.Deactivated:Connect(function()

Active.Value = false

end)

Explosion script for my part:

while true do

wait()

if script.Parent.Humanoid.Health == 0 then

local Explosion = Instance.new("Explosion")

Explosion.BlastRadius = 200

Explosion.Position = script.Parent.Position

end

end

Please format with Code block aka.

This

For easier reading!

The problem

I think what's going on in your region script is your calling RegionPart.Parent on objects you find in your region3. The problem with this is when objects get removed inside the area they are still referenced in code, but their parent is nil aka deleted. To get round this problem i would change the following code:

local RegionPart = game.Workspace.RegionPart
local pos1 = RegionPart.Position - (RegionPart.Size / 2)
local pos2 = RegionPart.Position + (RegionPart.Size / 2)
local Region = Region3.new(pos1, pos2)

while true do
	print("Started/Restarted Loop!")
	wait()
	local PartsInRegion = game.Workspace:FindPartsInRegion3(Region, RegionPart, 1000)
	for i, RegionPart in pairs(PartsInRegion) do
		if RegionPart.Parent:FindFirstChild("Humanoid") ~= nil then
			print("Found the Humanoid!")
			if RegionPart.Parent:FindFirstChild("Sword") ~= nil then
				print("Found the Sword!")
				if RegionPart.Parent.Sword:FindFirstChild("Handle") ~= nil then
					print("Found the Handle!")
					if RegionPart.Parent.Sword.Handle.Active.Value == true then
						print("Decreasing RegionPart's Health!")
						RegionPart.Humanoid.Health = RegionPart.Humanoid.Health - 30
					end
				end
			end
		end
	end
end

To:

local RegionPart = game.Workspace.RegionPart
local pos1 = RegionPart.Position - (RegionPart.Size / 2)
local pos2 = RegionPart.Position + (RegionPart.Size / 2)
local Region = Region3.new(pos1, pos2)

while true do
	print("Started/Restarted Loop!")
	wait()
	local PartsInRegion = game.Workspace:FindPartsInRegion3(Region, RegionPart, 1000)
	for i, RegionPart in pairs(PartsInRegion) do
		if(RegionPart.Parent ~= nil) then 
			if RegionPart.Parent:FindFirstChild("Humanoid") ~= nil then
				print("Found the Humanoid!")
				if RegionPart.Parent:FindFirstChild("Sword") ~= nil then
					print("Found the Sword!")
					if RegionPart.Parent.Sword:FindFirstChild("Handle") ~= nil then
						print("Found the Handle!")
						if RegionPart.Parent.Sword.Handle.Active.Value == true then
							print("Decreasing RegionPart's Health!")
							local HumanoidChk = RegionPart:FindFirstChild("Humanoid") --// check to see if this part has a humanoid if so lets damage it!
							if(HumanoidChk ~= nil) then
								RegionPart.Humanoid.Health = RegionPart.Humanoid.Health - 30
								--// this would be better and simpler to do the following
								--[[
								Un comment this section after removing the above code as both do the same thing.
The only difference between is your way will damage humanoid regardless if the humanoid has a forcefield or not but the way below allows for immunities with the ForceField aka doesn't damage the humanoid!
								HumanoidChk:TakeDamage(30)
								]]
							end
						end
					end
				end
			end
		end
	end
end

The rest of the code/scripts look fine!

Reference: https://developer.roblox.com/en-us/api-reference/function/Humanoid/TakeDamage

Hope this helps!