What does it mean?

來源: 2007-11-04 10:57:53 [舊帖] [給我悄悄話] 本文已被閱讀:

I just got Email from uscis as follows:

Application Type: I485

Current Status: Card returned by the post office as undeliverable.

On October, 2007, the post office returned our last notice as undeliverable. Please call 1-800-375-5283 to update the mailing address.

What does it mean? I do not change my address and check mailling box everyday, how can I do next?