FBX model fragmented in 30 pieces?



I have a problem with the FBX import from LensStudio,
my problem is the following:

I have a 3D model of clothing on Blender I export it respecting all the prerequisites
(https://docs.snap.com/lens -studio/references/guides/adding-content/3d/exporting-content/blender-3d-object-export#animation).

However when I import my model into Lens Studio it is fragmented into 30 pieces, which prevents me from assigning it to a full body mesh, I've been fighting this for hours and it's really very frustrating.