回复：关于绿卡--网上为什么查不到我们的号码

4 days after we sent the required document back, we checked the INS case status, which said they have received our RFE reply. After another 2 days, when we go back to INS website to check our status, it said, its not a valid case number.
Here is the complete message. Anybody had a similar situation before? Thanks a lot. Case number
WAC-02-167-XXXXX:
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Validation Error(s)
You must correct the following error(s) before proceeding:
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 submitted your application.
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