收到Name check 回複，then what?

My GC process is stuck in the name check process, so I made a Freedom of Information-Privacy Acts(FOIPA) request to FBI. Today I got the reply from FBI,

"......Based on the information furnished, a search of the automated indices to our central records system files located no records at FBI Headquarters responsive to your FOIPA request to indicate you have ever been of investigatory interest to the FBI.......

......In order to respond to our many requests in a timely manner,our focus is to identify responsive records in the automated indices that are indexed as main files. A main index record carries the names of subjects of FBI investigations.

Although no main file records responsive to your FOIPA request were located in our automated indices, we are required to inform you that you are entiled to file an administrative appeal if you so desire......"

My questions are: 1) What is administrative appeals? 2) Do I need to file such an appeal in order for the CIS to get my name check result?

Thanks!