Help! I-90 for GC replacement

Thanks for anyone who can help with advice.

485 approved and GC received in Aug. Name was wrong so GC was sent to CSC with I-90. Return Notice of Receipt from post office was received so it was certain that the package was received. But ever since nothing was heard from CSC, not even a receipt notice. At a complete loss as of what can be done.

Anybody has any idea? Thanks very much.