請問小白兔和PJIANG

I have filed I485 for me and my family on July 18. This morning I found the all checks were cashed. However, based on the receipt number on the back of the check, they gave me the number for I765 not I485 for me. The amount of the check is $395, and I have not filed I765. If I receive the mailed receipt and it is still wrong for I765, how can I contact with CIS to correct it? Thanks a lot