Rig pose won't show up in studio [Blender - ROBLOX]

[SupernovaDesign]

You can write your topic however you want, but you need to answer these questions:

1. What do you want to achieve?
   I want to import this Blender rig into Roblox and be able to animate it.
   

   

2. What is the issue?
   The gun is rigged to the hand, so it moves with the hand in Blender.
   

   
   
   When I use the Roblox custom rig import (FBX), it shows up like this:
   The pose is gone, and the gun doesn’t move with the hand:
   

3. What solutions have you thought of so far?
   I have applied transforms in Blender, but that didn’t help.

Any help appreciated

[SupernovaDesign]

Boosting the post, nobody replying