Need help , how i can get case status?

[usinsuser99]

Hello members.

Yesterday i got emails for approvals of mine & my wife
But in the case of kids 9 & 5 case status showing as follows.

"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."

Pleas give the adivses to me what i can do?
if any body got this type problems please share with me.
Iam little bit worring about that.

thanks in advance for sharing ur time with me.

My details.,
-----------
PD 10/10/02
ND 12/1/03
FP 11/9/04
LUD 11/16/04(FP RCVD)
LUD 11/24/04 (W/O MESSAGE)
LUD 12/22/04 (Approved for me & my wife)

first time kids LUD updated (after case received LUD) when clicked on their case showing above message.

thanks.,

usinsuser99