When I try to convert Polygons to Subdiv this error appear on script editor.
I try to cleanup it, but nothing change

Can someone help me please ?
// Error: polyToSubdiv1 (Poly To Subdiv Node): One or more edges is nonmanifold.
// Nonmanifold geometry cannot be converted to a subdivision surface.
// To clean up nonmanifold edges, use Polygons->Cleanup with the nonmanifold option. //
// Error: Command polyToSubdiv failed. Open Script Editor for details. //