Why is the merge mesh tool not working on imported usd file?

I am trying to use the merge meshes tool on my usd file but I’m getting this error message:

  /home/user/Omniverse/Library/isaac_sim-2022.2.0/exts/omni.isaac.merge_mesh/omni/isaac/merge_mesh/extension.py(221): _merge_mesh

2023-08-30 07:44:57 [3,113,695ms] [Error] [omni.ui.python] TypeError: 'NoneType' object is not iterable

where should I go looking for what’s missing or misplaced in the imported usd stage?

@salvo.dipp can you share a screenshot of your stage? there was a note from the doc that said:

In order to use the tool all of the meshes being merged must be under a single Xform.

there’s a short video from the doc as well in case further clarification is needed.

My meshes were under the same Xform. I don’t know why but after a while this issue fixed itself after I had to reinstall IsaacSIm for other reasons.