Called USCIS. Was told "Status for this Receipt Number cannot be xava2006-09-08 18:08:21

Just called USCIS. The system told me:

Status for this Receipt Number cannot be found at this time in this automated system. Please check your case receipt number to see if it is correct. If you have questions or concerns about your case status, please contact the service center where you ted your application.

Anybody has any idea?

Thanks.

回复：Called USCIS. Was told "Status for this Receipt Number can