After I485 application was filed in March, 2004, I got a CIS notice, saying that there was insufficient fingerprint fee for $50. It's an obvious error. Then, I collected all the copies of the related cleared checks,including the $50 one mentioned, and all the other supporting materials and wrote a letter. A month later, the CIS sent back the response,indicating the money is not needed, and returned the check, which I sent with the letter in case that they didn't cash out the previous $50.
It's already 3 months since then but the online status is still the same.Why didn't they change it after they verified everything and sent back the response? What should I do now? Any suggestion is highly appreciated. Thanks.