IndexError in _map_isolated_points

[ladvu]

I tried to simplify a mesh and maintrain its uv. However, I encounter this error:

File "/root/cvg/project/wcy/project/RemoteSensing/scripts/preprocess_data.py", line 58, in <module>
    preprocess(src, dst)
  File "/root/cvg/project/wcy/project/RemoteSensing/scripts/preprocess_data.py", line 19, in preprocess
    _, _, vmap = replay_simplification(mesh_in.vertices.view(np.ndarray).astype(np.float32),
  File "/root/miniforge3/envs/omages/lib/python3.10/site-packages/fast_simplification/utils.py", line 21, in wrapper
    return func(*args, **kwargs)
  File "/root/miniforge3/envs/omages/lib/python3.10/site-packages/fast_simplification/replay.py", line 198, in replay_simplification
    mapping, points_to_merge, outliers = _map_isolated_points(
  File "/root/miniforge3/envs/omages/lib/python3.10/site-packages/fast_simplification/replay.py", line 96, in _map_isolated_points
    mapping[merged] = mapping[target]
IndexError: index 49234 is out of bounds for axis 0 with size 49234

My code(functon preprocess):

def preprocess(src, dst):
    mesh_in = trimesh.load_mesh(src)
    texture = mesh_in.visual
    if isinstance(texture, trimesh.visual.ColorVisuals):
        return
    new_verts, new_faces, collapse = simplify(
        points    =mesh_in.vertices.view(np.ndarray),
        triangles =mesh_in.faces.view(np.ndarray),
        target_reduction= 0.75,
        return_collapses=True
    ) 
    _, _, vmap = replay_simplification(mesh_in.vertices.view(np.ndarray).astype(np.float32),
                                       mesh_in.faces.view(np.ndarray), collapse)
    new_uv = np.take(texture.uv, vmap)

    new_mesh = trimesh.Trimesh(
        vertices=new_verts,
        faces=new_faces,
        visual=trimesh.visual.TextureVisuals(uv=new_uv, material=texture.material)
    )
    
    new_mesh.export(dst)

Could you help me out of this?