Adjustment of Status - I-485

My marriage based application is still pending at the national benefit center so I asked my senator to help me make inquiry from Uscis.
This was the response I got ????

Director, Constituent Service
 
Re:
Name: Ekundayo Ogunnaike
Receipt Number: MSCxxxxxxxxxxxxxx
Form: I-485
 
Thank you for your inquiry regarding this constituent’s immigration matter. U.S. Citizenship and Immigration Services (USCIS) records confirm that your constituent’s case is pending at this time. USCIS is committed to adjudicating immigration benefits in a timely and efficient manner while also ensuring public safety, national security and compliance with all relevant directives. While the processing steps for most applications or petitions are completed quickly, a small percentage of cases involve unresolved issues that may result in adjudication delays. For example, if our review reveals an issue that may impact an individual’s eligibility for the requested immigration benefit, further inquiry is needed. The inquiry may include an additional interview and/or contact with another agency for updates or more comprehensive information.
 
We are unable to determine at this time when the review process for the application will be completed. USCIS will issue a decision on your constituent's case once certain issues are resolved. We are striving to resolve these issues as soon as possible.
 
We understand that Mr. Ekundayo may be frustrated by the progress of his case. However, USCIS must balance individual inconvenience against broader issues of public safety and national security.
 
We hope the information provided is helpful. If we may be of assistance in the future, please let us know.
 
Thanks,
U.S. Department of Homeland Security
U.S. Citizenship and Immigration Services
National Benefits Center
Lee’s Summit, MO
 
 Anyone has an idea the meaning of this ? My PD is 12/22/2016