Status for this Receipt Number cannot be found!!!

[usinsuser99]

Hello every one!!!

today i got emails of I 485 approvals for me & my wife.
But in case of my kids LUD updated 12/22/04

while clicked on their Case # , here iam getting following message.

CASE STATUS

The 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 National Customer Service Center.
National Customer Service Center (800) 375-5283.

could any body got this type of message. Please share with me
thanks in advance.

Regards
usinsuser99.