Problem with weights in fbx file

when I see the weights of my model in blender all seems to be fine, but when I export the fbx and import it in sketchfab the vertices move differently, like something was wrong with the weights of my model

This is how it looks in blender.

And this is how it looks when I import it in sketchfab.
I’ve tried to edit the weights in blender but stills the same.what can I do?

Hmmm, do you have any unapplied modifiers in your .blend file perhaps?

the only one is the armature modifier

@norgeotloic Any ideas?

i could change the bones or modify the weights

or I could modify the mesh too

I could solve it

It was because the arms had some weight in the stomach and chest