During non-peak times, funds are usually withdrawn on the payment date you specify, assuming your e-filed return has already been accepted (received) by the State.
Due to high e-filing volume, it can take a little longer to process the payment and then it can take your bank another few days to post the debit to your account.
No worries; as long as you selected April 18, 2017 (or earlier) as your payment date, you won't get penalized for a late payment. Since it has been more than 10 days after your return has been accepted, you can contact The State of New Jersey Division of Taxation at 609-292-6400 M-F from 8:30 am-4:30 pm for assistance in confirming the scheduled debit date.