N400 Inline for interview for 4 months, No news..HELP!

Hi everyone,

I filed my N400 June, 9th, 2017. My field office was St Louis, MO. I did my bio beginning of July at St louis, MO. Then I moved mid July. I have changed my address to Chicago, IL. July 25 my change of address request is completed. and my N400 status changed to "inline for scheduling interview" July 26, 2017.

I have not heard anything from USCIS since then.

I noticed a few people have their N400 filed in Sep and got their interviews already. I called the 800 number. I was told my case was still within the processing time.

What happened? Should I worry? What should I do?

Anyone who has similar experiences or advice, please help. Thank you so much in advance.
This has been my N400 timeline so far. I applied online from NJ, marriage-based application.

Jan 1 2018- N400 Online Application Filed
Jan 3 2018- USCIS N400 Receipt Notice
Jan 6 2018- USCIS N400 Biometrics Scheduled Notice
Jan 26 2018- Biometrics Completed
Jan 31 2018 - USCIS N400 Notice of Interview Scheduled
Mar 14 2018- Interview Date