NJ didn't begin to release refunds until March 1st, and the whole NJ refund process is slow this year. You can track your NJ refund with NJ directly after c March 19th :
https://www16.state.nj.us/TYTR_TGI_INQ/jsp/prompt.jsp
NJ refunds may not show up on this tracker until 4 weeks after e-filing (or more).
I would simply give it until March 20th.