I would go back there and see if you can speak with the officer that conducted the interview to make sure you have not missed anything. It would be helpful if you printed the on-line messages, but I understand that you may have not, especially that first one indicating that the request for RFE was sent. If you do not get anywhere, you may need an attorney to intervene.
This is not legal advice and a client attorney relationship is not created.
I would schedule an infopass appointment. It may also be worthwhile to submit a FOIA request to USCIS for your full "A-file." The FOIA request may reveal what is causing the hold-up. Good luck!
This information is provided for informational purposes only and does not constitute legal advice, or establish an attorney-client relationship.
It is good that you followed up by checking online. I would recommend that you contact the USCIS office where you were interviewed to let them know that you have not received the request for evidence and request that they send another one to you. Make sure that USCIS has your correct address. If you move file Form AR-11 AND contact the USCIS district office where your naturalization application is pending.
All the above answers are good, I would just add one thing to them: that is, document everything you are doing, send USCIS a letter in addition to calling and possibly visiting the Newark office. Put as much in writing as possible.