Name check, security check for I-485.

I have two I-485 forms pending, one for NIW and the other one for EB1A. USCIS told me that my two I-485 forms have been consolidated into one A file, but USCIS is waiting for my security check before they can process my I-485. I am puzzled that my name check has been passed one year ago
based on the Local office. Is security check different from name check? Thank you for your help.