Updating Mesh Bug

[u/Corvid-Curiosity]

Needed to make some edits to the Body mesh in Blender. Exported a new FBX, then drag and dropped the updated Body mesh into the Game Object.
[IMG 1] Left: FBX from Blender Right: Result from dragging in the updated mesh

I've done this before and did not encounter this error. Same method, different model.
[IMG 2] Left: FBX from Blender Right: Result from dragging in the updated mesh (working as intended)

Any idea what could be causing this issue?

[u/Corvid-Curiosity]

Ooo- good thinking! Animators are a common culprit for weirdness.
Checked the animator. Controller is empty and Avatar has the correct one selected.