Skinned Mesh material issue

Questions
1

Hello, hope you are having a great day!

I loaded an object file (glb), but it looks strange.

Could you anyone help me please?
Thank you in advance.

2

My guess is the normals are backwards for the face

3

@anidivr thank you for your answer.
So is it the problem with the model file? How can I fix it in Three.js?

4

Its usually a problem with the model file. To confirm, try the following to recompute the normals. If this doesn’t help, it must be something else.

geometry.deleteAttribute("normal"); 
geometry=BufferGeometryUtils.mergeVertices(geometry); 
geometry.computeVertexNormals();
5

I tried but the same issue.

6

I fixed this issue by creating a new material using its current texture.

gltf.scene.traverse((child) => {
        if (child.isMesh) {
          child.material = new THREE.MeshPhongMaterial({
            map: child.material.map,
          });
        }
      });

But still don’t understand what was wrong with its original material.