CollisionGroupId not changing on UpperTorso nor LowerTorso

Help and Feedback Scripting Support
#1

Hey there, I was trying to change the CollisionGroupId using a script, and it wasn’t working, shortly after I decided to check using the explorer, and the UpperTorso’s and the LowerTorso’s Id wasn’t being changed but every other Part’s Id was being changed, not sure why this is happening since my code is fairly simple and if any errors would be happening, I could solve it by looking at the output, but it simply shows nothing, I changed the Id of these two parts manually and got the correct collision behavior, which has me scratching my head, any help would be very useful. Here’s the code I used:

local Players = game:GetService("Players")

Players.PlayerAdded:Connect(function(Player)
	Player.CharacterAdded:Connect(function(Character)
		for _, Parts in ipairs(Character:GetChildren()) do
			if Parts:IsA("BasePart") then
				Parts.CollisionGroupId = 1
			end
		end
	end)
end)

I also tried changing the Collision group of these parts using game.PhysicsService:SetPartCollisionGroup(Parts, "GroupName") , but it offers the same result (doesn’t change UpperTorso’s or LowerTorso’s CollisionGroupId) so I have no idea what alternatives I have or if this is a bug.

Thanks.

CollisionGroup and CollisionGroupId don't match error
#2

Update: I added a line of code that prints the CollisionGroupId of each part along with their full name and I got this: [Classic Baseplate - Roblox Studio - Gyazo] then I check again using the explorer and UpperTorso and LowerTorso go back to 0 (Default), so instead of not changing, they do change but change back to default, this is very weird behavior that I have no idea what is being caused by, I’m trying this on an empty baseplate so no other scripts are interfering with the CollisionGroupId’s. I also tried it on R6 and it works fine, but I have no clue why it won’t work on R15, which is my game’s RigType.